"If you should ever be forced by a robber to withdraw money from an ATM machine, you can notify the police by entering your PIN # in reverse.
For example, if your pin number is 1234, then you would put in 4321.
The ATM system recognizes that your PIN number is backwards from the ATM card you placed in th machine.
The machine will still give you the money you requested, but unknown to the robber, the police will be immediately dispatched to the location."
It isn't is it?