Like many young men who ruled Wall Street back when high finance was a respectable profession, Vinny Pahuja figured that the stock market would be a bottomless source of riches. Right after graduating from NYU business school, with a dual major in finance and information systems, he landed at Lehman Brothers. Pahuja joined an elite crew on Lehman's internal trading floor, bringing in boatloads of money selling mortgage-backed securities. He earned $250,000 a year, weekended in South Beach, and picked up tabs for bottle service at upscale nightclubs. "I figured I'd be a baller for the rest of my life," Pahuja says. "What could be better?"

Then, as the woefully familiar narrative goes, the economy imploded and the titans of finance saw their gilded lives begin to vanish. "My bonus was going to be half of what it was the previous year," he says. In mid-2007, just as the securities he sold were reaching peak toxicity levels, Pahuja, 29, requested a sabbatical: He recognized that the current situation was unsustainable and wanted to get a jump on the impending exodus from Wall Street.

But instead of seeking a simpler or more stable life, Pahuja pursued a Plan B that involved high risk and equally high reward: poker. He had long been a successful recreational player, and, post-Lehman, he began focusing on the game full-time. His win rate increased dramatically. So Pahuja decided to make the sabbatical permanent. He won more than $600,000 in 2008—which landed him the 10th-place spot on Card Player magazine's Player of the Year list.

Using skills honed on the Street, he's turned poker into just one more exotic financial transaction. Now, though, instead of commuting to midtown Manhattan in a suit, he flies to Las Vegas for million-dollar tournaments or sits at home in boxer shorts, playing five online tables simultaneously. "Some friends have told me that my greatest trade ever was Lehman for poker," Pahuja says. "Other people act kind of snide about the fact that I gamble for a living. I shrug it off and tell them that I must be doing okay since I'm not one of the guys out there looking for a job. I'm making more money at poker than I could make on Wall Street right now."

It's not just the recently unemployed who've moved from monitoring interest-rate fluctuations on Bloomberg terminals to searching out games on Full Tilt—it's guys who still have jobs but are looking to make up for the shortfall in their once-hefty bonuses. One hedge-fund trader, who competes under the name chosenpromise, is compensating for a withered paycheck by playing high-stakes Texas Hold'em. "There is not as much immediate upside on Wall Street as there used to be," he says. "After things got bad I upped my poker hours significantly."

Though some ex–Wall Streeters prefer taking risks with other people's money, Pahuja enjoys putting his own on the line, believing that playing poker taps into his entrepreneurial side. Besides, with their shared reliance on probability, psychology, and swagger, playing the market and playing cards have always been two sides of the same coin. And in an era when an entire cohort of Ph.D.-level quants have been discredited as speculative fools, risking next month's car payment on a bluff seems like a perfectly reasonable application of statistical expertise. "More than ever before, I'm seeing a lot of my guys playing online poker," says Jin Zeng Joshi, a vice president at Dynamics Associates, a Manhattan-based executive-recruiting firm that focuses on the financial industry.