Jeff Skoll was eBay's employee number 2 and president number 1. He left with a comfortable fortune and a desire to spend his money helping others.

The Skoll Foundation, established in 1999, invests in, connects and celebrates social entrepreneurs -- offering grants to people who build businesses, schools and services for communities in need. Every year, it presents the Skoll World Forum on Social Entrepreneurship at Oxford, and runs Social Edge, a networking site for social entrepreneurs.

His production company, Participant Productions, is what Skoll calls a "pro-social media company," making features and documentaries that address social and political issues and drive real change. His film North Country, for example, is credited with influencing the signing of the 2005 Violence Against Women Act. Participant's blockbuster doc, An Inconvenient Truth, is required viewing in classrooms around the world, and has unquestionably changed the debate around climate change. Other Participant films include The Kite Runner, The Visitor, Food Inc., The Cove, and the recent Earth Day release, Oceans.