Soap made from human corpses
Raul Hilberg reports that stories about soap made from human fat were told in Lublin, Poland, as early as October 1942.  The Germans themselves knew about the stories.  Heinrich Himmler, the leader of the SS, got letter saying the Poles thought Jewish people were being "boiled into soap."  The letter also said the Poles feared they would also be used to make soap.  These stories were so widely known that some Polish people actually refused to buy soap. Himmler was so worried by the rumors, and the thought of poor security at the camps, that he said that all bodies should be burnt or buried as quickly as possible.