The incredible shrinking Mark Evanier on e-mail hoaxes. This past year, I got one from a well-meaning teacher friend that she was sending around our entire school system. I had to politely rebuke her and tell everyone that it was a scam.
Mark recommends the use of snopes.com to see if that e-mail you received about cell phone numbers being released to telemarketers is truly legit (which in most cases, it isn't). That site's kept me from sending a lot of get well cards to alleged "kids with incurable diseases" as well.