Now, for a real creeply but true part.
Decades ago they expanded Fort Rucker in Alabama and had to move a graveyard...it was reported that when they moved the deteroriated caskets that they discovered fingernails in the inside top of a number of caskets. It was determined that these people had a case of sleeping sickness. This is the same area where my mother and her relatives are from.
I can believe that! I have read other stories about people being buried that were not dead. There is not much I can think of that is worse than being buried alive.