A false pregnancy is a phallicsy. (from my friend Mitch, in college)

Knock, knock
Who's there?
Eskimo Christian Italian
Eskimo Christian Italian who?
Eskimo Christian Italian no lies. (from one of those little Peter Pauper Press books, but I don't remember which one.)

BTW, I seem to remember reading that knock-knock jokes originated in the era of speakeasies, with passwords at the door, etc. but I can't track down where I read it. If anybody runs across it, I'd appreciate knowing where. Thanks M