Before he dropped out of Harvard to build Facebook, Mark Zuckerberg was an officer at the Jewish fraternity Alpha Epsilon Pi, where the scrawny young computer geek had a ferocious nickname, according to a classmate.

"Slayer" was Zuckerberg's freshman frat name, his dorm-mate Rebecca Davis O'Brien writes in a Daily Beast profile of the Facebook CEO. If that makes geeky Zuckerberg sound rather unbelievably like a ladykiller, consider it might well have been a reference to his frat duties: As exchequer, Zuckerberg was responsible for collecting dues. He wouldn't launch Facebook — a move that finally brought him to the attention of various campus babes — until sophomore year. Even after that happened, "Slayer" became a better description for Zuckerberg's reputation with regard to privacy than with regard to the opposite sex, his dating life notwithstanding.

[Photo of Zuckerberg with his fraternity brothers and in his dorm room via Facebook]