Yup! It's called: Don't mess with old people!
An old man is called to his auditors office, as the auditor wants to know how he pays all his bills. With the old man is his attorney.
Auditor: You are 75 years old, you have no retirement fund, and no solid source of income. You say you get the money to pay you bills by gambling.
Old man: Yup, I'm a very good gambler you know.
Auditor: Maybe so, but you can't get all your money from gambling, what are you hiding?
The old man said again that he was a very good gambler, but the auditer was still doubtful. "Fine" said the old man "I'll prove it to you! I bet you $1000 that I can bite my eye."
The auditor, knowing this to be physically impossible agreed. So, the old man took ot his glass eye, and bit it. The auditor was highly surprised.
"Okay" said the old man "Now I bet you $2000 I can bite my other eye." The auditor, realising the old man was not blind, bet with him again. The old man promptely took out his false teeth, and bit his good eye. The auditor's mouth fell open in shock.
By now the auditor was fuming, he had just lost $3000 to an old man. The old man decided to make one last bet "How about we go double or nothing?I bet you $6000 dollars I can stand behind your desk, and pee into that wastebasket on the other side of the room, and not mess a single drop. The auditor, knowing this was impossible, and willing to try anything, reluctantly agreed. So the old man stood behing the auditor's desk and tried to pee into the wastebasket. But, try as he might, he couldn't get even a single drop inside the basket.
The auditor was ecstatic, and he whooped in joy and delight. Not only had he lost his $3000 dollar debt, he had also gained that much. He beamed from ear to ear.
Next to him, the old man's attorney groaned, and buried his face in his hands. The auditor, suddenly nervous, asks what's wrong.
The attorny replied: "It's just that, before we left to come to your office, the old man bet me $25 000 that he could piss all over your desk and you'd be happy about it!"