Ive been telling this one for years, I cant remember where I heard it. Jimmy had a problem. Jimmy sucked his thumb all the time, and his mother had tried everything to try to make him stop. She was talking to a friend of her's who said that she stopped her daughter from sucking her thumb by telling her that if she did, a big wart would grow in her stomach and grow so big it would kill her. Jimmy's mother thought this an effective method, and tried it on Jimmy the next day. As she relayed this to her son, his eyes grew wide, and he immediately stopped sucking his thumb, cold turkey. A week or so later, Jimmy and his mother were on the bus trying to find a seat. They made there way to the back of the bus where a 9 month pregnant lady sat. Upon seeing this, Jimmy pointed at the woman and blurted out: I know what you've been doing!
(From the "Rest" of RHF)