My old favorite quote:
"Isn't sanity just a one-trick pony anyway? I mean, all you get is that one trick, rational thinking, but when you're good and crazy, well, the sky's the limit!"– The Tick (comic book)
That one still sings to me but, I think I have a new favorite:
"Sucess is going from failure to failure without losing enthusiasm" - Winston Churchill
Oh that's good.