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 recognizes that your pin number is backwards from the ATM card
you placed in the machine.
The machine will still give you the money you requested, but unknown
to the robber,the police will be immediately dispatched to help you.
This information was recently broadcasted on TV and it states that it
is seldom used because people don't know it exists.
http://www.halfbakery.com/idea/Panic_20PIN 
I hope noone needs to use it but i do also hope if so it helps Tammy
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