After building a sprawling financial-services and media empire, Bloomberg LP, which employs 19,000 people and brings in annual revenue of about $9 billion, Bloomberg, who has two daughters, Georgina and Emma, from a previous marriage, has pledged to give away most of his personal fortune, estimated at $47.8 billion. Founded in 2006, Bloomberg Philanthropies boasts assets of $10 billion (the mogul himself so far has contributed $5 billion) and employs 120 people. As part of its environmental efforts, the foundation has donated more than $100 million to move America away from coal.