I've never hated or even disliked any of my cars. All were fun in their own way. My '63 Corvair Monza was my 'coming of age' car. Next was my '70 El Camino, then a '71 VW camper van, followed by a brand new '79 Camaro w/Highway Patrol package. A '72 El Camino and others followed.
Had shelves full of Revell models of cars and planes when I was a kid.
With the exception of car-jacking or home-invasion robberies, which involve surviving the ordeal and require possessing tools equal to or greater than those employed by the perp, security boils down to costing the thief enough time, that he becomes too nervous to finish or gets caught in the act.
Saying that a house is impregnable or a car can't be stolen is akin to saying the Titanic was unsinkable.
Most gun safes that weigh much under a ton or cost less than $3,000 are about as secure as that 6 year old condom that the teenage boys used to carry in their wallets.
About 18 years ago I had one of the honchos responsible for security at Universal Studios bragging to me about the brand new gate and parking structure cameras having bullet proof lenses. I said to him, "Are they paintball proof too"? It took him a few seconds, but he looked like he was about to cry. He pleaded with me not to say anything to anybody. I said, "I won't, unless they steal my truck".
Best anti-theft measure one can take on a newer vehicle today would be a cut-off (interrupt) switch (see Ian's post #5). Something car thieves don't expect to encounter.
As I understand it, OnStar, with the right gov't or law enforcement paperwork, can remotely shut down most any OnStar equipped vehicle manufactured after 2004, without any action by the vehicle occupant and in spite of any action taken by the occupant.
My 2 cents.