" rel="nofollow">jd writes: "According to the BBC, it is possible to remotely control the brakes, dashboard, car locks, engine and seatbelts. Researchers have actually done so, with nothing more than a packet sniffer to analyze the messages between the onboard computer systems and a means of injecting packets. There is no packet authentication or channel authentication of any kind, no sanity-checking and no obvious data validation. It appears to need a hardware hack, at present — such as a wireless device plugged into the diagnostics port — but it's not at all clear that this will be a limiting factor. There's no shortage of wireless devices that must make use of the fact you can inject packets to turn on/off the engine, lock/unlock the doors, track the car, etc. If it's a simple one-wire link, all you need is a transmitter tuned to that wire."
A budget is just a method of worrying before you spend money, as well