Ouch, after reading some of these, I feel less bad about posting some Doug Stanhope jokes.
I personally like the first and last here:
http://www.youtube.com/watch?v=XQZWA-T3nbs
Or if you don't like videos:
Hey, so I told my girlfriend I wanted to fuck her between the tits, she said, "How're you gonna make that feel good for me?", I said, "Right before I cum I'll stop punching you in the face."
and...
I had a girl say this to me. She goes "you know, if god intended women to suck dick, he'd made cum taste like chocolate" I said "Yeah, but he had to make it taste like bleach so you remember to do the laundry"