I know I'm sick and twisted...

...can't help it. Laughed my ass off at this one:

I was walking past the mental hospital the other day and all the patients were shouting ,"Thirteen!....Thirteen!....Thirteen!"

The fence was too high to see over, but I saw a little gap in the planks and looked through to see what was going on.

Some bastard poked me in the eye with a stick!

Then they all started shouting "Fourteen!...Fourteen!...Fourteen!"

(Thanks, SusieQ!)