According to an urban legend, the name of the inventor of the modern toilet. Totally bogus, of course.

''Not according to the company he founded.  According to them, 'crap' (feces) didn't come from his name, but crapper (toilet fixture) did:''

http://www.thomas-crapper.com/history02.htm

He wasn't the inventor of the toilet, but he was the one who made his mark with it, rather like Ford's assembly line or Bill Gates' operating systems.  Crapper was a good businessman.