Larry Summers (Larry Summers/AP Photo)

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Top speaking fee: $135,000

You know Larry Summers as the former U.S. Treasury Secretary — okay, you know him from "The Social Network" — but the popular economist is also a big catch on the public speaking tour. Summers' fees start low, as little as $10,000 for a speech he gave to Yale University in 2009, but can quickly skyrocket, such as the $135,000 Goldman Sachs paid the former Harvard president to appear at a corporate function that same year. According to The Wall Street Journal, Summers earned some $2.77 million in public speaking cheques in 2009 alone, including a $45,000 sum he was given by Merrill Lynch, which he reportedly donated to charity.

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