Followers: 3.3 million
Sample tweet: "I'd breed my own dinosaur and come riding in on a baby Triceratops complete with a bedazzled saddle. #mygagaentrance"
Saturday Night Live cast member turned late-night host Jimmy Fallon was one of the first television personalities to use Twitter to his advantage. By tweeting monologue jokes before the show airs and sharing his favorite viral videos, Fallon has created a massive online fan base, with more than 3 million Twitter followers. That's more than any other late-night host, making Fallon the Twitter king of TV comedy.