My point was actually that there already is a disconnect for the starter, which is the starter solenoid. That's what the MasterLock gadget does, but with extra bells and whistles like a remote. The same thing could be done with a hidden switch or an aux output from a car alarm. Just use a decent relay, not the cheap shit that car alarms come with. Order a brand-name Bosch, NAiS, Omron, etc., and pay the $8 to $20 from an electronics distributor (you'll pay that much at a store for a cheaper type). You don't want to be stranded on the side of the road because of a cheap relay on your fuel pump, ignition, etc. I've seen it happen, and it's probably a pain in the ass.

The Braille switch is very cool, but it looks too easy to bypass based on the way it appears to mount. Anything easy to install is easy to remove or easy to bypass.