Earwigs

Sometimes called pincher bugs, earwigs have a very nasty legend attached to them. The rumor is that they will crawl into your ear while you are sleeping and begin munching a path through your brain.

What would most likely happen is the bug would get stuck in your ear canal and panic, then claw frantically for an exit. If this happens, I highly recommend having a doctor remove it. It will be like an itch that won't go away, but the bug will probably exhaust itself to punctuated squirms long before you get to the emergency room.

The rumor has origins in an old skit horror show and involved a caterpillar, not an earwig.