Bill Gates, policy adviser for the new Obama administration?

Post-retirement, Gates has been taking a more active role in politics. While he has ruled out political office, that doesn't mean he's not influencing the administration's stance from behind the scenes. On foreign aid, funding for diseases like HIV/AIDS and malaria, childhood education, and even broadband access, Gates has been making his voice heard.

In December, Gates had a sit-down with Vice President-Elect Joe Biden and others in the Obama transition team, urging them to support programs on education and global poverty even in the midst of the recession.

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Would you vote for this man? Gates talks policy in DC last month.

"I think we were very encouraged that the transition team and the incoming administration is likely to be quite strongly focused on things we think are important," says Geoffrey Lamb, a former World Bank director who now manages the Gates Foundation's public policy. "We got the strong sense there was wide agreement there had to be reform of public education, which pulled more disadvantaged, lower performing schools into the net of achievement ..."

Gates gets a welcome reception in the other Washington, but not because of connections. "People don't see you in Washington because you have lunch with them regularly," Lamb said. "They see you because they think you have something valuable to contribute."

Gates' own political contributions have run the gamut, from Democrats Patrick Leahy and Max Baucus to Republicans Arlen Specter and Congressman Dave Reichert.

As a private foundation, the Gates Foundation is restricted from lobbying, but it spends about 10 percent of its annual contributions on advocacy. That includes educating legislators, communicating with regulatory bodies and informing the public, according to the foundation.

"What you're finding is that more and more, as these philanthrocapitalists are getting more experienced, they're seeing that they need to get better and better at the leverage, particularly about how you use advocacy and public opinion to change policy," says Matthew Bishop, the author of Philanthrocapitalism. "So they're going more and more into politics."