Most of the posts involve actual code examples, and may be hard to follow if you've never done any programming; some of them, however, will generate a WTF? reaction in just about anyone.
BRUSSELS - The Dexia Bank ATM machines are experiencing a curious problem. The machines stop functioning when someone enters the number 7, making it impossible for people with a 7 in their pin (personal identification number) code to perform a cash withdrawal.Oops.
The Daily WTF: Curious Perversions in Information Technology