Here's a long one and it's much better when told in person:

A Russian wrestler came to the United States and within six months, he was the heavyweight champion of the world. Although he wasn't a particularly talented wrestler, he had developed a submission hold that he called the "pretzel hold." It was named after the shape of his opponent's body after the hold was applied. Once applied, the hold was supposedly impossible to break. An old-time wrestler who was managing an up and coming wrestler decided the only way he would ever make enough money to retire was to develop a countermeasure for the pretzel hold and then get his young wrestler a match with the Russian. He took out $5,000 of his $10,000 savings and set up a special training camp. He bought every photo and film which showed the pretzel hold being applied. He and the young wrestler then set about to develop the countermeasure. After six months, they finally concluded that there was no countermeasure--that once it was applied, the match would be over. While discouraged, the manager also knew that his wrestler knew more about the pretzel hold than anyone else. He was also twice the wrestler that the Russian was and the manager believed that his kid could avoid the pretzel hold and beat the Russian. He negotiated a shot at the title and finally arranged a match at Madison Square Garden. The odds against his young wrestler winning were 100 to 1 so he took his remaining $5,000 and spread it around among bookies so the odds wouldn't drop. Finally the night of the match arrived. The manager was warming his wrestler up and started with his pep talk. He said, "You know kid, this is your big break. All you have to do is stay away from the Russian when he starts the maneuver that signifies the pretzel hold is about to be applied. You know what it looks like and just get out of the ring if necessary. Once you see your chance, pin him and then you'll be the champ. And, kid, I've spent my life savings on this. I've got $5,000 bet on you at a 100 to 1 and I'll be rich and be able to retire if you win. Can you do it kid, can you?" The kid replied, "I can do it boss. Nobody knows more about the pretzel hold--I can beat him, I know I can." Soon they are in the ring, the announcements are made and the bell rings. Much to his horror, in less than one minute the manager sees pretzel hold being applied. Well, he's devastated--all his money is gone and his kid has lost the championship. Crying, he turns away and starts out of the arena. About half way to the locker room, he hears a great roar from the crowd. Turning, he finds that somehow his kid has broken the pretzel hold and has the Russian pinned. Much to his amazement, the 3-count is made and his kid has won. He runs back to the ring and grabs the kid and hugs and kisses him. "Oh my God kid," he says, "I thought the match was lost and I couldn't watch anymore. I didn't see what happened after the pretzel hold was applied. Tell me kid, how did you do it?" "Well," the kid says, "I was just dumbfounded when all of a sudden I found myself in the pretzel hold--I didn't even see it coming. And boss, the pain was so terrible that I can't even begin to describe how bad it hurt. Just as I was about to throw in the towel, I looked up and I saw two hairy testicles hanging right in my face. Well boss, I thought, what the hell. I stretched up and I bit those testicles for all I was worth. And you know what boss? You can do most anything when you bite your own testicles."