"Transference of Pain" joke
One day a women was having a baby, and she asked the doctor "What can you do for the pain, for I've heard having a baby hurts a lot.", then the doctor told her he had a option for her. She could transmit some of her pain to the father of the baby, so the women and her husband agreed to give it a try.
So the doctor tried giving the husband 25% of the pain, and he felt no effect, so the doctor and the couple decided to give the husband 50% of the pain instead. Well, he still felt no pain, so the doctor increased it to 100% of the pain.
In the end of the birth, the baby was crying, the mother relived to have no pain and the husband had felt no pain at all. In the next few days, they all came home from the hospital and found the mailman dead on the porch!
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