A doctor was retiring after 30 years of saving all the foreskins from the circumcisions he had performed. He talked to a leather worker, who told the doctor he would be able to make something out of all those foreskins. A couple of days later the leather worker calls the doctor and tells him to come pick up what he has made. The doctor gets there and the leather worker gives him a wallet. The doctor says all those foreskins and all you could make was a wallet?! The leather worker tells him yea, but if you rub it, it turns into a suitcase.