Bill Gates and Warren Buffett have convinced 38 other billionaires to give away half their wealth to charity. Gates and Buffett started "The Giving Pledge" earlier this year; it’s a campaign to get the richest people to donate to the charitable causes of their choice, either before or after their death. Others taking the pledge include Michael Bloomberg, Barry Diller, Larry Ellison, T. Boone Pickens, David Rockefeller, George Lucas, Ted Turner, and Ronald Perelman. The U.S. has about 400 billionaires; the 40 who’ve made the pledge are worth more than $230 billion combined.
