More than one doctor has found their theories dismissed by the existing establishment, only to be proven right years later. Perhaps none of those stories are more dramatic than the story of Werner Forssmann, who, when faced with defeat, simply chose to go around everyone and do his experiment anyway - on himself.
In Time for Halloween. A 3500 year old Babylonian tablet gives the first known description of how to get rid of a ghost. It involves two dolls and beer.