Followers: 1.7 million
Sample tweet: "My son and his girlfriend are currently having a lightsaber battle using apps on their Android phones. I'm such a proud geekdad right now."
As if his portrayal of Star Trek: The Next Generation's Wesley Crusher wasn't proof enough of actor Wil Wheaton's geek cred, his Web popularity index should be. From his well-read blog that has inspired multiple books on his life growing up as a geek to his status as a devoted topic on the community site Fark, Wheaton's nerd influence is widespread. His tweets are revered musings on everything from Star Trek to comics.