Chuck Feeney is a rags-to-riches billionaire who's famous for giving away most of his fortune (which he made, incidentally, by inventing duty-free shopping. I kid you not). By 2016, he will have given $7.5 billion to help people on five continents get educated and healthy. You've probably never heard about him. He doesn't like to brag. But he's helped lots of people without making them wait for him to kick the bucket. It's a good thing, too — he's 83 years old in 2014 and still going strong.