Among the outsiders, Nassim Nicholas Taleb, 49, is the polemicist-in-chief. Famed for hectoring audiences of bankers (who invite him to speak and pay his five-figure speaker fees) and aggressively countering negative reviews of his work, Taleb gained a cult following when he published Fooled by Randomness: The Hidden Role of Chance in the Markets and in Life in 2001. It was, naturally, a screed that detailed how Wall Street deludes itself and investors with neat predictive models that regularly get blown apart by reality.

In 2002, Malcolm Gladwell profiled Taleb in The New Yorker, focusing on his investment in cheap, out-of-the-money options, betting that the market underestimated the likelihood of crashes. Then he shot to stardom with the publication of The Black Swan: The Impact of the Highly Improbable in May 2007, which extended his critique of risk management on Wall Street. Taleb argued that the models used to measure and contain risk were inherently flawed because they did not—and could not—take into account the existence of black swans, or unpredictable, potentially disastrous events.

Taleb’s timing was exquisite: The book hit shelves just months before banks started announcing billion-dollar writedowns on their subprime holdings. The Black Swan hovered at the top of the New York Times best-seller list, was translated into more than 27 languages, and won Taleb an appointment as Distinguished Professor of Risk Engineering at New York University, a custom-fit title he’s quite proud of. “It’s the highest title that they bestow in the department,” he says.

To Taleb’s way of thinking, the worldwide response to the 2008 crash has only made the economy more vulnerable to black swans. “The same analysis I made in 2006 holds stronger today with even more force,” he says. “It’s worse on both fronts. We have a swelling of contingent liabilities and hidden risk. We may be, cosmetically, growing things, but our liabilities and our debt are growing, too. I am expecting that things will only get worse because we wasted too much time not repairing the system. We are in an unprecedented time.”

For pure bombast, Taleb’s only rival is Marc Faber, who publishes the Gloom, Doom and Boom Report from his home in Hong Kong. Since 2002 the 64-year-old, Zurich-born economist has been predicting that the dollar would plummet in value, and since 2005 that an economic meltdown was about to hit the U.S. Faber now expects a sovereign-default domino effect, and he's not much rosier on China, saying in a Bloomberg Television interview that its economy might "crash" within the year. As for the S&P, he expects it to drop as much as 15 percent in the next six months. How will we cope with all this turmoil? In the June 2008 issue of Gloom, Doom and Boom, he recommended that Americans can help themselves by partaking in “prostitutes and beer” because they are “the only products still produced in the U.S.”