Sheldon
Sheldon is a bonafide geek. And then some. Like his flatmate and fellow physicist Leonard, Sheldon possesses scientific intelligence in abundance, but when it comes to common sense, he certainly drew the short straw. As a rule, he doesn't really get sarcasm. In fact, quite often Leonard has to help him out with it.
Sheldon attended boarding school as a result of his work with lasers, and not, as Leonard incorrectly assumes, following a series of experiments that set out to prove that, "If the height of a single step is off by as much as two millimetres most people will trip". Yes, Sheldon really does know how to party.
If you thought Sheldon was all about the physics though you'd be wrong. He's an avid fan of Battlestar Gallactica and a MySpace devotee (he's got 212 friends and everything). What's more, Sheldon loves to play a bit of Klingon Boggle with his friends, but hey, who doesn’t?