The following commentary comes from an independent investor or market observer as part of TheStreet's guest contributor program, which is separate from the company's news coverage.NEW YORK ( Insider Monkey) -- Raj Rajaratnam's trial is set to begin today. He made $200 million in 2007, barely missing the list of "highest paid hedge fund managers." Don't feel sorry for him though. He made the list in 2000. Art Samberg topped the Wall Street's Highest Earners list with $150 Million. Art Samberg is another hedge fund manager who has been charged with insider trading. He was lucky though, Pequot and Samberg agreed to settle the SEC's charges without admitting or denying anything. Hedge fund managers are the smartest investors around. They leave less to chance than most investors. They go great lengths to get an "edge" over ordinary investors. Insider Monkey, your source for free insider trading data, follows corporate insiders because they have access to material, nonpublic information and they sometimes trade based on it. We also follow hedge fund managers because they have the resources to do extensive research on public companies and they have access to experts who can guide them. We believe we are more likely to beat the market by imitating insiders and hedge funds than trading against them. Based on the transactions of nearly 700 hedge funds, we compiled the list of top 10 stocks hedge funds were buying like crazy during the fourth quarter: 1. General Motors ( GM): Hedge funds snatched 6% of GM's outstanding shares and amassed a $3.4 billion position. There were 112 hedge funds with GM positions at the end of December. John Griffin's Blue Rigde, William Ackman's Pershing Square, George Soros, David Tepper's Appaloosa, Roberto Mignone's Bridger Management, Richard Perry's Perry Capital, and Leon Cooperman's Omega Advisors are among the several high profile hedge funds with GM positions. 2. Citigroup ( C): Citigroup is hedge funds' most favorite mega-cap bank. Hedge funds, 190 of them, own 8% of outstanding Citigroup shares. During the fourth quarter, they spent $2.8 billion on Citigroup shares. Steven Mandel's Lone Pine, Bruce Berkowitz's Fairholme, Lee Ainslie's Maverick Capital, George Soros, Bill Miller's Legg Mason Capital Management, Bill Ackman's Pershing Square, David Tepper's Appaloosa, Daniel Loeb's Third Point, Andreas Halvorsen's Viking Global, Richard Perry's Perry Capital, Joseph DiMenna's Zweig-DiMenna, Leon Cooperman's Omega Advisors, Brevan Howard, and John Paulson's Paulson & Co are among the prominent investors who are bullish about Citigroup.