Conan O'Brien

Twitter handle: @ConanOBrien

Date joined: Feb. 24, 2010

Followers gained in 24 hours: 200,000+

The former Late Show host needed little assistance drawing a huge Twitter crowd, pulling in more than three times the number of followers than nemesis Jay Leno. If he’s not expressing his unflappable sense of humor, he’s tweeting exclusives like the first official photo from the Arrested Development movie set.