The act of slamming a penis onto the top of someone's head. Not to be confused with a cock slap, a sausage hammer relies on downward motion (as opposed to the side to side). Very effective when used to shock or surprise someone, very degrading when used during fellatio.
Mike typically gave Matt a sausage hammer in the locker-room every day prior to track
Will gave Cassie a sausage hammer after she failed miserably at fellatio.