I've just read all the extensive replies to this thread, and wanted to throw in my standard boilerplate 2c...

The best theft deterrent is to not leave anything worth stealing. That's why the empeg is so great: It's a pullout. Pull it out and take it with you, and you won't have a need to alarm or boobytrap your car.

If you want to go the extra mile, make sure all of your equipment is stealth-mounted. For instance, speakers go under factory grilles or hidden under upholstery, amps hidden in spare-tire wells, etc. The hole in the dash can be covered by a dash plate (mine is the official Honda part with the Honda logo on it), and a would-be thief looking at your car thinks there's no stereo to steal.

Things like alarms and boobytraps are "after the fact" retaliations in the war against theft. It's better just to stay out of the war completely.

And athough the boobytrap ideas are fun, I certainly wouldn't feel comfortable driving a boobytrapped car. You never know when it's going to "false".

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Tony Fabris