Best T-Shirt Slogan?

[anaxcrosswords]

I've just ordered a design-it-yourself t-shirt for my daughter. Using the KEEP CALM AND... template I've gone for BLAH BLAH and BLAH BLAH.

What's the funniest t-shirt slogan you've seen (or indeed invented yourself)?

[Prudie]

I was given a personal one which I like, it says 'Don't make me use my teacher voice'

[askyourgran]

Seen worn by a small boy. 'I am a mushroom, they keep me in the dark and feed me ***.'