If you find yourself saying “It may or may not be true, but…” stop and search Snopes. Snopes isn’t infallible, (Snopepedia anyone?), but it is very simple to check urban legends there.
Recently a few bloggers have written about comments “supposedly” (ha!) spoken by Bill Gates. But they aren’t his.
As a corollary, when you hear ,” stop before repeating it. Don your skeptics hat. What they’re really saying is “I don’t know, and I didn’t investigate it thoroughly enough to be able say for sure one way or the other.” Don’t compound the error.