Oh, and there's more.
Warren Buffet, the second richest man in the Universe, is also giving his entire and just slightly less massive fortune than Bill Gates' away for the benefit of mankind. In fact he's given most of it to Bill Gates!
FORTUNE Magazine: Warren Buffett gives away his fortune - Jun. 25, 2006
Top men, I reckon.
Bet you thought that would never happen in your lifetime.