"The six deadbolt theory"

Install six deadbolt locks on your front door, but only lock 3 at any one time. The theory is that the burglar is going to try all 6, thereby "locking" 3 and unlocking 3. So when he gets number 6 unlocked, he thinks he's in and then, *buzzer sound*, no dice.

Never heard it 'til I read it on /.

Interesting at least. It sounds good until the mofo breaks a window to get in.