Humourous graffiti:

In the beggining was the word and the word was aardvark.
the only useful tory is a lavatory.
sex appeal- please give generously.
disembowelling takes some guts.
(In a urinal) Your family's future lies in your hands.
down with gravity!
Van gough was ear.

"My mother made me a homosexual"

..and scrawled underneath:
if I gave her the wool would she knit me one!?

surely you would use mince instead of wool, just a thought lol.