Methodically collect datasheets for various garage openers for many years. Then, assemble a very powerful transmitter (connecting something like a metallic bridge or telephone pole for an antenna) that would broadcast (powered by a large capacitor bank charged from your car battery) a short but extremely powerful sequence of pulses that would flip through a vast number of possible garage codes for each brand of opener. Very quickly hide/destroy the machine. Result: a city of open garages.-- dsm, Jul 03 2001 This evil genius must be stopped! Is there a Super Hero with outbuilding related superpowers in the house?-- StreetLight, Jul 03 2001 Great plan... but whats the point?-- RobertKidney, Jul 03 2001 random, halfbakery