97. David Shaw
Shaw started out as a Columbia professor but left academia for Wall Street in the 1980s, using his computer science background to become a pioneer in quantitative finance. He founded hedge fund D.E. Shaw in 1988, and the firm counts luminaries such as Jeff Bezos (No. 2) and John Overdeck (No. 122) among its alumni. Shaw has since turned over the day-to-day operations of his $43 billion business, opting to lead a team on computational biochemistry research instead. He also is back to teaching at Columbia.