i bought a 1978 porsche 911sc exactly one week before my then-wife told me she was pregnant. there is no way (in our financial situation at the time) that i could have justified buying it (even at the fairytale price i did) one week later. well, almost exactly one year later, as i walked out to the car to drive to work one morning, i found an empty spot where the 911 used to be. the officer who came and took my report told me not to worry, that it was just being joyridden, and would be found in a couple days. incredulously, i looked at him and said, 'what? you think this is an accord?' well, i was right. about five weeks later, the passenger compartment of the car was found dumped in a ditch out in the countryside, and the sheriff of that county found me via the VIN. all the tasty bits (front and rear suspension/brakes, engine, and transaxle) had been cut away with a sawsall and cutting torch.
well, i know that a fiat spider is not as high-value a target, but i am still a bit nervous about ever parking it outside. and btw, being divorced, having way more income, and owning a mazda3, i had no difficulty in justifying my spider purchase.

my question:
have any of you installed any type of ignition interrupt or something that requires one to press a hidden button in order to start the car? i have seen it done on a couple of porsches and one old ferrari, but don't know the best way to go about it on a spider. if anyone has some advice, i am all ears.
as for recovering the car if it does ever get stolen, i don't want to go into any details about location and wiring, but my old iphone 4s, a dirt-cheap data-only plan via ting wireless, and the 'find my iphone' app on my new phone will give me almost all the info i need. i mean, i certainly have gangster-movie type fantasies of calling up the boys and converging on the garage where my stolen car is, but in reality i would just call the police and meet them there.