Mr Turismo try this one - especially for you!
A reporter goes to a mental institution to do a story. He's walking around when he sees a man swinging a baseball bat. He walks up to him and asks, "Buddy, What the heck are you doing?".
The man replies, "I'm Babe Ruth. One more home run and I'm outta' here."
The reporter just nods and walks on. He sees another guy swinging a golf club on the other side of the room. He walks over and says, "Excuse me, but what the heck are you doing?"
The guy says, "I'm Tiger Woods. One more hole in one and I'm outta' here."
The reporter just nods and walks away. Then he sees another guy in the corner with a peanut on the end of his penis. He goes over and asks the guy what he thinks he's doing and the guy replies, "I'm f***ing nuts and I ain't never getting outta' here!"
I think it is rather patronising to assuming that mentals and disableds dont have a sense of humour! Im in the British Army I can vouch for a large number of blokes who really mental and still laugh their clocks off every day!