The Hawtin brothers run the Derwent Absolute Return Fund Ltd which bases its trading activity on sentiment it gathers from tweets around the world.

FORBES: Hedge Fund Uses Your Tweets To Predict Market Movement

The absolute return segments of the Titan Global Return Fund have not been hit as hard, but are still down by some 33% in 2010, says a person familiar with Titan Capital.

FORBES: Russell Abrams' Hedge Fund Accused of Fraud Amid Losses of 70%

Morningstar's "long-short" mutual-fund category includes market-neutral and absolute-return funds, which are designed to generate returns in any market environment, and arbitrage funds, which try to exploit market inefficiencies.

WSJ: Mutual Funds That Act Like Hedge Funds