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20. Oprah Winfrey

A hug—or a plug—from O on The Oprah Winfrey Show is pretty much all you need to spur sales of anything, be it scented candles or obscure novels. The first female black billionaire in U.S. history, Winfrey started out as a local talk-show host; today, she runs an influential, if comparatively small, media conglomerate that publishes books and produces television shows, movies, and radio programs.

THE STAT: Winfrey is now estimated to be worth almost $3 billion.

By Portfolio.com