damn you are good! you should get that out for sale man!
how about making the threads metal and using a complicated 240 volt setup, if they get it wrong they get a new hair do?
Which reminds me, I was playing a game on new years morning, 4 of you hold a handle type thing with a button on it each.
These are connected to a glowing button on a base, you press this button and when it changes colour you have to press your button, if you press last you get electrocuted, great game, 20 quid gadget shop

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