The Ottawa Herald's got a good story about a bank teller stopping a young mother from falling into a secret-shopper scam. She could've lost nearly $3,000.
How it works: Mom was supposed to deposit a cashier's check and spend the bulk of it on money orders at Wal-Mart, which she'd then send to the scammers. Except the mom would've been on the hook for the original cashier's check, which was a fake.
(Hat Tip: Thanks to Elaine Adams!)