One morning not long ago, a team of analysts at a major New York bank walked into work and found their lives turned upside down. The IT department had set up Web-browsing restrictions on all of their computers. Suddenly the young financiers could not access their personal email accounts. Suddenly they could not G-chat.

It didn't take long for one of the guys — a math-minded "quant," who had 20 years experience writing code — to work out a small program to override the restriction. "We ran it on our computers, it saved some files in the right places and then changed our Internet configuration so that it circumvented the security," said one of the analysts who benefited from the heroic hack. Ever since, he has been happily chatting and sending emails to friends using a hard-to-read, black-and-green Gmail scheme called "Matrix," which makes it so that supervisors walking by his desk think he's running some highly technical DOS-based financial model.

This is what freedom looks like in 2010 for young people working at large corporate firms around the city that have been cracking down on employees' Internet use. According to a spokesman for the Web-filtering-software firm Websense, most of their New York clients are motivated by security. The issue isn't necessarily productivity, he said — it's that Web sites that accept user-generated content are particularly vulnerable to "malicious injections."

And so, as social media and the Web in general become increasingly crucial tools for New York's ruling class, analysts at banks, paralegals at law firms, even employees of some news organizations and publishing houses must endure Web restrictions that are shaping their lives, isolating them from friends and generally disconnecting them from the outside world.

"It's tough dealing with that when you're fresh out of college and you're still interested in the world," said Alec Liu, a 24-year-old who worked as an analyst at the New York office of a European bank before quitting finance for an internship at Motherboard.TV. Mr. Liu said his two years in finance — where his Internet use was severely limited — left him feeling separated from friends and the culture at large. "To lose a pretty big chunk of your life — it was frustrating," he said.

In some offices, filters are in place to prevent people from visiting sites like eBay, Craigslist and Amazon, and from reading Gawker, Dealbreaker and ESPN. In others, every computer comes with a timer that clicks on whenever an employee calls up a self-publishing platform like Tumblr and Blogspot. That system sets a limit on how much time can be spent at those sites, forcing some particularly motivated bloggers to draft posts offline in Microsoft Word before logging on very briefly — so as to use as little time as possible — to put them up.

Aarti Kapoor, a Harvard '07 graduate, has been dealing with Web restrictions since she went to work for Citigroup out of school. Not only was her Gmail account off limits — so were YouTube and the celebrity news blogs she liked to check. Because Ms. Kapoor didn't yet have an iPhone, her only time for personal email was at home, late at night. When she started looking for a new job, the typically endless hours she was spending in the office meant that she had to respond to time-sensitive emails from headhunters at 3 o'clock in the morning.

Eventually Ms. Kapoor left Citi for a boutique investment bank where Internet use was regulated much less vigorously. It was great for a while. But recently, as the firm has grown, the same old restrictions have started popping up even there.

"Investment banking is notorious for its challenging hours and lack of work-life balance," Ms. Kapoor said by phone the other night, fresh off a 135-hour work week. "On an average day, you have maybe two hours to yourself, so it would be nice to not waste that precious time on perfunctory tasks, like responding to emails, which you could have otherwise handled during downtime at work."

The luckiest, or perhaps most industrious, of the afflicted find ways around the various blocks imposed upon them from the top. On some systems, typing in "https" in your browser's location bar instead of just "http" lets you see a stripped-down version of Facebook. If you add Gmail as a "gadget" on your "iGoogle" account, you can take advantage of some basic email functions. Some have figured out how to rig Google Reader as a communications device, sharing articles with friends and leaving "notes" they wouldn't want to be caught transmitting over their work addresses.

Internet-hungry 20-somethings trade tips, and commiserate with one another whenever the monitoring software catches onto a glitch and a loophole is sealed. A 24-year-old named Nick who used to work as a paralegal at a top 100 law firm recently remembered the day he found a way to liberate G-chat using the "https" trick.

"I discovered it by accident — I typed it in just to see what would happen," he said. "G-chat popped up and there was much rejoicing."

These days, of course, most people working corporate jobs have smart phones. But while it would seem a personal smart phone would be a person needed to set him/herself free, the fact is the devices can both alleviate your sense of isolation and exacerbate it. A Goldman Sachs analyst said she has become troublingly dependent on her smart phone, which she uses for email, G-chat, Twitter and Facebook.

"It's getting bad," the 27-year-old said. "I sit at my desk on my iPhone instead of with my hands on my keyboard. It's bad, but it's my only portal to the outside world."

FOR ALL THE tricks that have been discovered and passed around, blocks do work. A 25-year-old named Alexander who works for a news organization described the psychological maneuvering that governs his Web surfing as a process of self-denial. Until very recently, the computers at Alexander's office were equipped with a timer allowing him to spend a total of 60 minutes per day looking at blogs hosted by Tumblr and Blogspot. He could use the time in six 10-minute intervals, forcing him to constantly make judgment calls as to whether a link or a post was worth the entrance fee.

"It was use it or lose it," Alexander said. "A lot of consideration would go into deciding, 'O.K., is there going to be a substantive amount of information for me to read on this Tumblr? Are there going to be archives that I'm going to want to spend 10 minutes on, or is this literally just one LOLcat?'"

Though the timer system seemed to give Alexander more freedom to surf than his friends who worked at banks and law firms, it served as a very effective deterrent. "The quota system shames you into feeling like this is a waste of time," he said. "It's almost like when a parent says, 'Well, go ahead, I'm not going to stop you from staying out late and not doing your homework-see what happens.' It's like Foucault! Knowing that someone is out there judging you causes you to police yourself."

Not everyone who is subject to restrictions perceives it as a form of mind control, however. Rahul Kamath, who works on the trading floor for the Japanese bank Nomura, said the other day that while most of his friends who work outside of the financial sector are accustomed to the idea that daytime social networking is a right rather than a privilege, he doesn't have time for such dilly-dallying in his work day.

"I'm never on G-chat," Mr. Kamath said. "That part of my persona does not exist. I don't have a blog. I don't have a Twitter account. I'm not in touch with people in that high-frequency way, and a big part of that is because of the very specific nature of what I do. ... Me, personally, I don't really give a shit about that too much. I don't need to be doing personal stuff all day at work.

"All my Brooklyn friends are on Gmail all day, G-chat all day. It's understood," Mr. Kamath continued. "Because of the intensity of my job, because it's so oriented to market hours, it just doesn't make sense for me to spread myself that thin, attention-span-wise.

"It is a sacrifice," he said, "but here's the thing: I'm getting paid to be there."

lneyfakh@observer.com

With additional reporting by Esther Zuckerman