Linked from Openbook is this article on Business Insider that quotes a 19-year-old Mark Zuckerberg, having just launched the original 'The Facebook', as saying the following:
Zuck: Yeah so if you ever need info about anyone at Harvard
Zuck: Just ask.
Zuck: I have over 4,000 emails, pictures, addresses, SNS
[Redacted Friend's Name]: What? How'd you manage that one?
Zuck: People just submitted it.
Zuck: I don't know why.
Zuck: They "trust me"
Zuck: Dumb fucks.