You would be amazed and scared if you knew what can be done with dealer level software on a modern car.The worst part(actually kind of good if you want to wrench on your own car)is there are plenty of cracked versions floating around for most makes.There was just a thing on the news in BG about how they just break the window of high end luxury cars,plug in and away they go.Cars that where supposed to be theft proof are now easier targets for thieves in the know in europe.
I personally have dabbled in modifying the bosch ecu on my Audi with a friend who does aftermarket tuning,and even for a non tech savy guy like me it is super simple to defeat the immobilizer,change programming etc etc.Just with free software off of the net and some time on this forum
http://nefariousmotorsports.com/forum/ Granted that forum wont tell you how to do this,nor is it whats needed to do such things,it just goes to show what info is out there.For me I use RossTech's program for diagnostics etc and with this and some time I could do most of what these guys show just through my diagnostic port no need to remove the dash
