Thomas Boone Pickens, Jr., 82 (born May 22, 1928)
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Thomas Boone Pickens, Jr., also known as T. Boone Pickens, founded what became Mesa Petroleum in 1954 and built it into a major independent oil company during his 40 years there. During the past 15 years, he has become an active investor through BP Capital and TBP Investments Management, firms he heads. The colorful tycoon has given away an estimated $700 million.