Funniest T-Shirt Ever

I was just reading Mark Morford's latest column about his Christmas wish list and he mentioned what is the funniest t-shirt slogan I've heard of in a long, long time.

Via T-Shirthell (which I cannot view from my school connection) the slogan is:
"Every time you see a rainbow, God is having gay sex"

Guaranteed to cause your narrow-minded associates and family paroxysms. And also pretty damned funny.

My personal favorite for a t-shirt or bumper sticker is "Are you evil or just stupid?"