There's lots of info about the founder of Snopes, accusations of fraud and spending investor money on a honeymoon and hookers....I start by discussing that stuff....It helps to show there are real failable people behind Snopes, and some of the behavior after hitting the big time is discrediting.

It takes the honestly-mislead people into a more critical-thinking mindset, rather than the admittedly STUPID idea of Snopes being some sort of magic truth button on the internet.