Julia just wrote an interesting post about a piece of nonsense a dentist told her co-worker: Scientology and... Mint?.
It reminded me of a story I was told a few years ago. A friend of mine who was a musician, and consequently had long hair, got into a conversation with a guy on a plane and the subject of Scientology came up. The man said, "But you can't be a Scientologist. You have hair." When my friend asked him what he meant the man told him that he'd been told Scientologists had to shave their heads.
The epidemic of mis-information about Scientology is easily remedied. Just check out some actual sources such as the Scientology Video Channel or the Dianetics Video Channel.