Here's a fun one - ever hear anyone say that if they were wrong about something they'd eat their hat? I personally love that one and use it often, but I never knew where it came from. The first popular use of the phrase is from 1837 in Charles Dickens' The Pickwick Papers:
"If I knew as little of life as that, I’d eat my hat and swallow the buckle whole.”But where does it come from? I found a reference to a pork stew made of mostly the bits of meat that no one would eat otherwise referred to as hatte stew. I'm not positive on this one, but the fact that hats called pork-pie hats became popular in the 1830's makes me wonder if there is in fact a connection there.
Pork > Yucky Stew > Pork Hats > "I'll eat my hat (the yucky bits) if I'm wrong."