Nil alivd quam pictura mota.
Lit: It is nothing less than a moving picture.
Col: It's only a movie!
"I don't know if I am going to be able to do this" never gets old. Also, "I hope this isn't going to crash the server someday" gives me a warm feeling late at night.
"If the fucker doesn't cost your your life, it isn't a quest." Which I lifted from gapingvoid.com
An ex-coworker used to (half-facetiously) say that his mantra was, "You're doing it wrong."