Top 10 scams of 2011
Top check cashing scam
Identify it: Scammers contact you via a Craigslist posting to buy your old couch. They send you a check for more than the amount they owe you, and they ask you to deposit and then wire them the difference via Western Union. A deposited check takes a couple of days to clear, while wired money is gone instantly. When the original check bounces, you are out whatever money you sent and you're still stuck with the old couch.
Avoid it: Use a secure service like PayPal when dealing with online purchases. If someone does send you a check for more than they owe, send it back. That old couch can wait.