Top hedge fund managers made money in many ways last year, from investing in overseas stock markets to betting that prices of commodities like oil, wheat and copper would rise. Some, like Mr. Paulson, profited handsomely from the turmoil in the mortgage market ripping through the economy.

As early as 2005, Mr. Paulson began betting that complex mortgage investments known as collateralized debt obligations would decline in value, much as Wall Street traders bet that shares will drop in price. In that case, known as shorting, they borrow shares and sell them, wait for the price to fall, buy the shares back at a lower price and return them, pocketing the profit.

Then, over the next two years, Mr. Paulson established two funds to focus on the credit markets. One of those funds returned 590 percent last year, and the other handed back 353 percent, according to Alpha. By the end of 2007, Mr. Paulson sat atop $28 billion in assets, up from $6 billion 12 months earlier.

Mr. Soros, one of the world’s most successful speculators and richest men, leapt out of retirement last summer as the market turmoil spread  and he won big. He made $2.9 billion for the year, when his flagship Quantum fund returned almost 32 percent, according to Alpha. Mr. Simons, a mathematician and former Defense Department code breaker who uses complex computer models to trade, earned $2.8 billion. His flagship Medallion fund returned 73 percent.

Image James H. Simons, once a code breaker, made $2.8 billion. Credit... Hiroko Masuike for The New York Times

Like Mr. Paulson, Philip Falcone, who founded Harbinger Partners with $25 million in June 2001, cast a winning bet against the mortgage market. He pulled in returns of 117 percent after fees in 2007 and made $1.7 billion. The trade thrust him from relative obscurity to hedge fund heavyweight: he now manages $18 billion. Harbinger recently won agreement from The New York Times Company to add two members to its board.

Hedge fund managers share their success with their investors, which include wealthy individuals, pension funds and university endowments. They typically charge annual fees equal to 2 percent of their assets under management, and take a 20 percent cut of any profits.