In App Land, Lots of Ways to Get a Ride

In Monday's Times, Brian X. Chen writes about the legal struggles of Uber, whose app connects users with car service drivers. Uber has captured the fancy of many riders but faces opposition from regulators and the taxi industry. While the company is perhaps the most prominent tech start-up looking to shake up the car service and taxi industries, it is not alone. Here is a quick look at the approaches being pursued by various companies.

SMARTPHONE CAR SERVICES: Uber, its main competitor Taxi Magic, and smaller outfits like Cabulous essentially work as dispatch systems for existing black car or taxi services. Regulatory scrutiny has led to a patchwork of coverage across the country. Taxi Magic, for instance, has not been able to move into markets like New York, and operates a parallel service, Sedan Magic, which offers a slightly different (and more expensive) service.

PEER-TO-PEER RIDE SHARING: SideCar and Lyft, which operate in the San Francisco area, allow pe ople to give strangers rides in their own cars. The companies pitch their services as something of a hybrid between a capitalistic transaction and a social opportunity.

Sunil Paul, the founder of SideCar, says that because the drivers do not necessarily get paid - a fare is negotiated for each ride and is referred to as a donation - the drivers are not professionals, and thus not subject to the same regulation as taxis and black car services. The California Public Utilities Commission disagrees, and recently levied $20,000 fines against SideCar and Lyft, along with Uber, for operating without licenses. Mr. Paul says that the companies are meeting with the commission soon to try to resolve the dispute.

“We are using a new medium, and we need new rules,” Mr. Paul said.

TAXI SHARING: A number of start-ups have tried to create services that would allow people to share taxis, but for the most part they did not reach the critical mass needed for a rider to re liably find people with which to share. Weeels, a New York-based start-up that eventually admitted defeat and pulled its app from the iTunes store, is working on a specific population: people waiting on the taxi line at La Guardia Airport's Terminal C on Sunday nights and Monday mornings. An attendant uses a private iPad application to group riders going to various parts of the city. The system proved helpful in the week after Hurricane Sandy. Weeels said it arranged about 20 rides an hour during peak times in the days after the storm, when cars and gas were particularly scarce.

David Mahfouda, one of the company's founders, said that it will expand at La Guardia first, then look to broaden its services. “We're starting from a particular problem and building up to a generalized transportation solution, and not vice versa,” he said.

PEER-TO-PEER CAR SHARING: If SideCar and Lyft are an informal alternative to taxis, RelayRides and Getaround are similar alternat ives for car rentals. Drivers can arrange to rent their own cars to strangers when they are not being used. While the practice has raised some legal questions about whether insurers could drop drivers who participate, the companies say they have not faced the same type of opposition as the car service start-ups.

Disruptions: Silencing the Voices of Militants on Twitter

Twitter, perhaps more than any other social media outlet, has become one of the most powerful tools to promote democracy in the Middle East.

The service, which helped fuel the Arab Spring protests and a new order in the region, is now under attack for aiding and abetting terrorist organizations.

Along with six other Republican lawmakers, Representative Ted Poe, a judge turned Texas Congressman, sent a letter to the F.B.I., demanding that Twitter ban two militant groups, Hamas and Hezbollah, that are on the State Department's list of terrorist organizations. “Failure to block access arms them with the ability to freely spread their violent propaganda and mobilize in their war on Israel,” he said in a statement to news outlets, adding: “The F.B.I. and Twitter must recognize sooner rather than later that social media is a tool for the terrorists.”

The demand is based on laws saying that any person or group offering material support - contributing ca sh, weapons and other tangible aid, including “service” and “expert advice or assistance” - to terrorist organizations is essentially working with them.

But some might argue that running AK-47s and rocket launchers to terrorists, and using Twitter, which allows groups to post 140-character missives online, are two very different things.

In a phone interview, Mr. Poe was adamant that Twitter had a responsibility to take down the accounts. By having a voice on the site, he said, they “are amassing more followers and threatening the security of the United States.”

“We freeze terrorist organizations' bank accounts, and we ought to freeze their Twitter accounts, too,” he said.

But civil liberties lawyers are wary of such actions. “The problem here is the process by which the government decides to classify a terrorist organization,” said Michael C. Dorf, a constitutional law professor at Cornell.

The material-support provision has been used to convict about 75 people in the United States, but it remains a contentious issue right up to the Supreme Court.

“The more immediate set of concerns is that not everything these groups do is terrorism, and there are people whose speech could be restricted by some of these laws,” Professor Dorf said, adding that people associated with Hamas who offer aid and education to Palestinians would be silenced, too. “So it's hardly a slam dunk to say that the statute covers Twitter or Facebook.”

Although the letter to the F.B.I. was sent in September, the request gained more attention in recent weeks as fighting escalated in Gaza. After Israel killed Hamas's top military commander, Hamas unleashed an increased barrage of missiles. Both Hamas and a press officer for the Israel Defense Forces posted to Twitter to describe the strike as it unfolded.

Israel has also used other social networks: it has shared videos on YouTube, updated its Facebook sta tus to say which members of Hamas it had killed, and in the most bizarre move, created mood boards on Pinterest to show off its troops and weapons. Banning Hamas or Hezbollah on Twitter could set a broad precedent.

For civil libertarians, any move to remove Hamas and Hezbollah from Twitter raises concerns.

“I think it's as contrary to the First Amendment as openness is the enemy to extremism and fundamentalism,” said Jonathan Zittrain, a professor at Harvard Law School and a founder of the Berkman Center for Internet and Society. “The F.B.I. is going to learn more about Hamas and any organizations, by having them operate in an open environment, than if its voice is driven to proxies and underground backchannels, which would inevitably happen immediately.”

Hamas and other groups don't fall under the Constitution of the United States. for many of the countries in the Middle East, Twitter is the closest thing to a democracy that gives people a voice, e ven if it's one that we don't always agree with.

E-mail: bilton@nytimes.com

Download: Biz Stone

An interview with Biz Stone, a founder of Twitter who doesn't follow anybody on Twitter.

Field Notes in Ergonomic Diversity: Standup Workers Speak

Dr. Michael Roizen marches, in steady, measured steps, at the forefront of the upright workers movement. That “movement” is not a union uprising, but a reference to the growing numbers of office workers who are rising from their chairs to stand, even walk, for health reasons.

Dr. Roizen, the chief wellness officer at the Cleveland Clinic, has been a personal proponent of not sitting at work for years - before the accumulation of recent research on the hazards of sitting for hours, and before the proliferation of standing and treadmill desks in the last few years, which I wrote about on Sunday.

Dr. Roizen typically works at a treadmill desk for hours a day, and his short health-tip videos are called “Treadmill Talks.” In these Web videos, he delivers his advice while walking on the treadmill, as in this one.

He is an advocate of the 10,000 steps-a-day regimen for better health, and his treadmill desk helps him reach and surpass that goal. “For me, this setup is a way around inactivity,” he said.

Doesn't trekking on a treadmill hamper office work? The secret is to get the pace right, he said. Dr. Roizen has experimented on himself, and found he can effectively handle conference calls while walking at 3.3 miles per hour, typing to reply to e-mails at 1.8 mph, and more serious writing at 1.7 mph.

Standers, though, outnumber treadmill walkers. Patrick Skerrett, managing editor of Harvard Health Publications, is a committed stander. Until recently, the few people who stood while doing office work were those trying to combat chronic back pain. And many companies still require a letter from a doctor, describing some ailment, before they offer an alternative to the office chair.

But today, many workers who stand up for part of the day do it because they enjoy the diversity of positions, and it makes them feel better and more alert - like Mr. Skerrett. Two years ago, he bought an inexpensive, adjustable -height desk, which he paid for himself. In an eight-hour day, he says he will stand for perhaps six hours. “Sometimes, I sit down because I'm tired of standing,” Mr. Skerrett said. “It's all by choice.”

The recent research that points to the health hazards of extended sitting has prompted some standers. Pam Gotto, executive assistant to the president of the Marshfield Clinic, got an adjustable desk that allows her to sit or stand about a year ago, after reading studies on sitting-related risks. Ms. Gotto, 46, has been an administrative worker for the Wisconsin health provider for 26 years, and “ninety nine percent of that time was sitting,” she said. Today, he moves up and down, standing about 20 percent of the time. “Whenever I get tired of sitting, I stand,” she explained.

Working while standing was an adjustment. “But I quickly got used to it, and I would never go back,” Ms. Gotto said.

Chairs, of course, are not enemies. “Even if you took all the chairs away, as humans we would find a way to sit,” said Dr. James Levine of Mayo Clinic, a leading researcher in the field of inactivity studies. The problem, as with so many things, is a matter of degree - sitting too much. The research suggests that damage begins after a person is sitting continuously for an hour or more.

So regular breaks, standing and walking around, seem commonsense advice. “Find ways to restructure activity into the day,” said Dr. Toni Yancey, a professor of health services at the University of California, Los Angeles. When meeting with a colleague, take a walk and talk, she suggests. Some companies, she adds, have begun scheduling in a couple of 10-minute group exercise breaks in the workday. “It's an oasis in the middle of a stressful day,” she said.

Establishing habits and routines of movement and activity in the day, Dr. Yancey said, are key. “If it's not your default option, it tends not to happen,” she said.

And there is no one-size-fits-all formula. Dr. Yancey, for example, has a treadmill desk at work, but mostly she pedals away on a recumbent exercise bike while working at home.

The Brain Behind Brain Pickings

She's Got Some Big Ideas

Elizabeth Lippman for The New York Times

Maria Popova is the editor of Brain Pickings, an online grab bag of eclectic information.

SHE is the mastermind of the one of the faster growing literary empires on the Internet, yet she is virtually unknown. She is the champion of old-fashioned ideas, yet she is only 28 years old. She is a fierce defender of books, yet she insists she will never write one herself.

Maria Popova grew up around books.

At precisely 9:30 on a chilly Saturday morning, Maria Popova slips out of her apartment in Brooklyn, scurries down a few stairs and enters a small basement gym. A former recreational bodybuilder from Bulgaria, Ms. Popova is the unlikely founder of the exploding online emporium of ideas known as Brain Pickings.

Her exhaustively assembled grab bag of scientific curiosities, forgotten photographs, snippets of old love letters and mash notes to creativity - imagine the high-mindedness of a TED talk mixed with the pop sensibility of P. T. Barnum - spans a blog (500,000 visitors a month), a newsletter (150,000 subscribers) and a Twitter feed (263,000 followers). Her output, which she calls a “human-powered discovery engine for interestingness,” has attracted an eclectic group of devotees including the novelist William Gibson, the singer Josh Groban, the comedian Drew Carey, the neuroscientist David Eagleman, the actress Mia Farrow and the Twitter founders Biz Stone and Evan Williams.

“She's a celebrator,” said Anne-Marie Slaughter, a Princeton professor and former State Department official. “You feel the tremendous amount of pleasure she takes in finding these things and sharing them. It's like walking into the Museum of Modern Art and having somebody give you a customized, guided tour.”

Unlike most blogger celebrities, however, Ms. Popova revels in remaining anonymous, which means her followers know almost nothing about her. In an age when many tweet what they put in their morning coffee, she rarely uses the word “I.” Her personal history is almost completely absent. Her photograph is not on the site. “I don't feel the necessity to be in the public eye that way,” she said after reluctantly agreeing to sit for an interview. “There's a certain safety in making people feel like you're an organization and not a person. ”

A fierce creature of habit, she begins every day by working out. On this morning, she alternates 20 chin-ups with 50 push-ups, then performs a series of planks and stretches. Once on the elliptical, she frantically highlights an obscure 1976 book, “The Creativity Question” (Amazon sales ranking: one million-plus), and checks her RSS feed on her iPad.

Exactly 70 minutes later, she returns to her modest one-bedroom apartment to write a brief essay about Freud and daydreaming, file her thrice-daily blog entries and schedule her regimen of 50 Twitter messages a day. She does this while balancing on a wobble board.

“I try to sit still when I work, but my mind goes spiraling elsewhere,” she said in a mild Slavic accent reminiscent of Bond girls in the 1970s. “When my body is moving, it's almost like it takes the wind out of this mental spinning, and I'm able to focus.” Recently, she came upon a 1942 book on inspiration chronicling others with the same habit. “Mark Twain paced while he dictated,” she said. “Beethoven walked along the river. Maybe there's a psycho-biological element.”

Ms. Popova traces her discipline to her upbringing behind the Iron Curtain. Her parents met as teenage exchange students in Russia and had her almost immediately. Her father was an engineering student who later became an Apple salesman; her mother was studying library science. “We're not very much in touch,” she said of her parents today, “but recently we were on Skype, and this whole library science thing came up. I realized a lot of what I do is organizational, almost like a Dewey Decimal System for the Web. My mother got so emotional. It was very funny, and kind of moving.”

Her paternal grandmother was a rabid biblio and had a collection of encyclopedias, Ms. Popova said, and she credits the act of randomly opening volumes and happening upon entries for her passion to discover old knowledge. “The Web has such a presentism bias,” she said, with Facebook updates, tweets and blog entries always appearing with the latest first. By contrast, flipping through the encyclopedia was “an interesting model of learning about the world serendipitously and also guidedely.”

After graduating from an American high school in Bulgaria, she enrolled at the University of Pennsylvania, where she quickly grew bored with what she calls the “industrial model” of education, involving large-scale lectures. While still a student, she was working part time at an advertising firm in 2005, when a colleague sent around an e-mail with clippings of rivals' work to inspire the team.

Bruce Feiler's latest book,“The Secrets of Happy Families,” will be published in February. “This Life” appears monthly.

A version of this article appeared in print on December 2, 2012, on page ST1 of the New York edition with the headline: She's Got Some Big Ideas.

Taking a Stand for Office Ergonomics

Stephanie Diani for The New York Times

Dr. Toni Yancey, professor of health services at U.C.L.A., gets work done while riding a recumbent bicycle at home. She also uses a treadmill desk at the office.

THE health studies that conclude that people should sit less, and get up and move around more, have always struck me as fitting into the “well, duh” category.

But a closer look at the accumulating research on sitting reveals something more intriguing, and disturbing: the health hazards of sitting for long stretches are significant even for people who are quite active when they're not sitting down. That point was reiterated recently in two studies, published in The British Journal of Sports Medicine and in Diabetologia, a journal of the European Association for the Study of Diabetes.

Suppose you stick to a five-times-a-week gym regimen, as I do, and have put in a lifetime of hard cardio exercise, and have a resting heart rate that's a significant fraction below the norm. That doesn't inoculate you, apparently, from the perils of sitting.

The research comes more from observing the health results of people's behavior than from discovering the biological and genetic triggers that may be associated with extended sitting. Still, scientists have determined that after an hour or more of sitting, the production of enzymes that burn fat in the body declines by as much as 90 percent. Extended sitting, they add, slows the body's metabolism of glucose and lowers the levels of good (HDL) cholesterol in the blood. Those are risk factors toward developing heart disease and Type 2 diabetes.

“The science is still evolving, but we believe that sitting is harmful in itself,” says Dr. Toni Yancey, a professor of health services at the University of California, Los Angeles.

Yet many of us still spend long hours each day sitting in front of a computer.

The good news is that when creative capitalism is working as it should, problems open the door to opportunity. New knowledge spreads, attitudes shift, consumer demand emerges and companies and entrepreneurs develop new products. That process is under way, addressing what might be called the sitting crisis. The results have been workstations that allow modern information workers to stand, even walk, while toiling at a keyboard.

Dr. Yancey goes further. She has a treadmill desk in the office and works on her recumbent bike at home.

If there is a movement toward ergonomic diversity and upright work in the information age, it will also be a return to the past. Today, the diligent worker tends to be defined as a person who puts in long hours crouched in front of a screen. But in the 19th and early 20th centuries, office workers, like clerks, accountants and managers, mostly stood. Sitting was slacking. And if you stand at work today, you join a distinguished lineage - Leonardo da Vinci, Ben Franklin, Winston Churchill, Vladimir Nabokov and, according to a recent profile in The New York Times, Philip Roth.

DR. JAMES A. LEVINE of the Mayo Clinic is a leading researcher in the field of inactivity studies. When he began his research 15 years ago, he says, it was seen as a novelty.

“But it's totally mainstream now,” he says. “There's been an explosion of research in this area, because the health care cost implications are so enormous.”

Steelcase, the big maker of office furniture, has seen a similar trend in the emerging marketplace for adjustable workstations, which allow workers to sit or stand during the day, and for workstations with a treadmill underneath for walking. (Its treadmill model was inspired by Dr. Levine, who built his own and shared his research with Steelcase.)

The company offered its first models of height-adjustable desks in 2004. In the last five years, sales of its lines of adjustable desks and the treadmill desk have surged fivefold, to more than $40 million. Its models for stand-up work range from about $1,600 to more than $4,000 for a desk that includes an actual treadmill. Corporate customers include Chevron, Intel, Allstate, Boeing, Apple and Google.

“It started out very small, but it's not a niche market anymore,” says Allan Smith, vice president for product marketing at Steelcase.

The Steelcase offerings are the Mercedes-Benzes and Cadillacs of upright workstations, but there are plenty of Chevys as well, especially from small, entrepreneurial companies.

In 2009, Daniel Sharkey was laid off as a plant manager of a tool-and-die factory, after nearly 30 years with the company. A garage tinkerer, Mr. Sharkey had designed his own adjustable desk for standing. On a whim, he called it the kangaroo desk, because “it holds things, and goes up and down.” He says that when he lost his job, his wife, Kathy, told him, “People think that kangaroo thing is pretty neat.”

Today, Mr. Sharkey's company, Ergo Desktop, employs 16 people at its 8,000-square-foot assembly factory in Celina, Ohio. Sales of its several models, priced from $260 to $600, have quadrupled in the last year, and it now ships tens of thousands of workstations a year.

Steve Bordley of Scottsdale, Ariz., also designed a solution for himself that became a full-time business. After a leg injury left him unable to run, he gained weight. So he fixed up a desktop that could be mounted on a treadmill he already owned. He walked slowly on the treadmill while making phone calls and working on a computer. In six weeks, Mr. Bordley says, he lost 25 pounds and his nagging back pain vanished.

He quit the commercial real estate business and founded TrekDesk in 2007. He began shipping his desk the next year. (The treadmill must be supplied by the user.) Sales have grown tenfold from 2008, with several thousand of the desks, priced at $479, now sold annually.

“It's gone from being treated as a laughingstock to a product that many people find genuinely interesting,” Mr. Bordley says.

There is also a growing collection of do-it-yourself solutions for stand-up work. Many are posted on Web sites like howtogeek.com, and freely shared like recipes. For example, Colin Nederkoorn, chief executive of an e-mail marketing start-up, Customer.io, has posted one such design on his blog. Such setups can cost as little as $30 or even less, if cobbled together with available materials.

UPRIGHT workstations were hailed recently by no less a trend spotter of modern work habits and gadgetry than Wired magazine. In its October issue, it chose “Get a Standing Desk” as one of its “18 Data-Driven Ways to Be Happier, Healthier and Even a Little Smarter.”

The magazine has kept tabs on the evolving standing-desk research and marketplace, and several staff members have become converts themselves in the last few months.

“And we're all universally happy about it,” Thomas Goetz, Wired's executive editor, wrote in an e-mail - sent from his new standing desk.

A version of this article appeared in print on December 2, 2012, on page BU3 of the New York edition with the headline: Taking A Stand For Office Ergonomics.

John McAfee Plays Hide-and-Seek in Belize

Photo Illustration by The New York Times

John McAfee, right, a pioneer in computer security who lives in Belize, is a “person of interest” in the murder of his neighbor.

AMBERGRIS CAYE, Belize

DANIEL GUERRERO promised during his campaign for mayor here to clean up San Pedro, the only town on this island, a 20-minute puddle jump from the mainland. But if he ever runs for re-election, don't expect him to mention that vow.

“I meant clean up the trash, the traffic, that sort of thing,” he says. “I didn't mean this.”

“This” is a full-blown international media frenzy and the kind of mess that no politician could have seen coming. It started on Nov. 11, the morning that Gregory Faull, a 52-year-old American, was found dead, lying face up in a pool of blood in his home. He had been shot in the head. His laptop and iPhone were missing. A 9-millimeter shell was found nearby.

What happened next turned this from a local crime story to worldwide news: The police announced that a “person of interest” in the investigation was a neighbor, John McAfee, a Silicon Valley legend who years ago earned millions from the computer virus-fighting software company that still bears his name.

A priapic 67-year-old, with an improbable mop of blond-highlighted hair and a rotating group of young girlfriends, Mr. McAfee quickly melted into the island's lush green forest. Then, for Belizean authorities, the real embarrassment began.

Asserting his innocence, Mr. McAfee became a multiplatform cyberdissident, with a Twitter account, and a blog at whoismcafee.com with audio links, a comments section, photographs and a stream of invective against the government and the police of Belize. He has done interviews on podcasts, like the “Joe Rogan Experience,” and offered a $25,000 reward for information leading to the arrest of “the person or persons” who killed Mr. Faull. He has turned lamming it into a kind of high-tech performance art.

“I am asking all people of conscience to read this blog, especially the links in the ‘Background' section,' and see the ugly truth unfolding here,” he posted on Nov. 18. “Speak out. Write your congressmen. Write the prime minister. Do what you can.”

Before he went underground, Mr. McAfee led a noisy, opulent and increasingly stressful life here. He was known for the retinue of prostitutes who he says moved in and out of his house, and for employing armed guards, some of whom stood watch on the beach abutting his house. He also kept a pack of untethered dogs on his property who barked at and sometimes bit passers-by.

Two days before the murder, someone had poisoned a handful of those dogs. As it happens, Mr. Faull had complained about the animals, as well as the guards and the constant late-night inflow and outflow of taxis on the dirt path that runs behind his and Mr. McAfee's homes - a path so tiny that it's supposed to be off-limits to cars.

Mr. Faull had shown up at the town council office a few weeks ago with a letter decrying the din and the dogs, as well as Mr. McAfee's guns and behavior. Nothing came of it.

“We were planning to meet with John McAfee and hand him the letter,” Mr. Guerrero said. “But it never happened. We were busy doing other work.”

In hindsight, that looks like a blunder. Mr. McAfee has since said on his blog that he had no choice but to flee because police and politicians in Belize are corrupt and eager to kill him. As proof, he has written at length about a late April raid that the country's Gang Suppression Unit conducted at a property of his on the mainland, in a district called Orange Walk.

Some McAfee watchers have a different theory - namely, that he grew paranoid and perhaps psychotic after months of experimenting with and consuming MDPV, a psychoactive drug. These experiments were described in detail by Mr. McAfee himself, under the pseudonym “Stuffmonger” in a forum on Bluelight, a Web site popular with drug hobbyists.

So, here's one hypothesis: Rich man doses himself to madness while seeking sexual bliss through pharmacology. Then shoots neighbor in a rage. Case closed, right? Ah, but those Bluelight posts were a ruse, Mr. McAfee would later blog, just one of the many pranks he has perpetrated over the years - part of a bet with a friend to see if he could create Bluelight's largest-ever thread.

A version of this article appeared in print on December 2, 2012, on page BU1 of the New York edition with the headline: Hide-and-Seek in Belize.