How tech founders are trying to disrupt -- and replicate -- the Giving Pledge

Silicon Valley billionaires can make promises to give away fortunes to charity. Why can't the rest of us? The Giving Pledge is the brainchild of some of the most prominent elders of Silicon Valley -- people like Bill Gates, Pierre Omidyar, and Larry Ellison -- who made billions of dollars in the first wave of tech giants only then to pledge to give most of it away. Silicon Valley, though, thrives on disruption. And in an age when billionaires are on the ropes -- and when tech leaders are reckoni...