There are only four purposes for computers in an automobile:
- Navigation
As seen in IMDB:Goldfinger. GPS and computerised maps tell you where you are.
- Performance
The engine of the modern automobile is controlled by a computer, and one of the first articles in Wired was about people who replace the regulating chip with one that gives them better performance. If you replace that chip with a computer interface, you can tailor performace to the conditions, on the fly. At the very least, you can monitor conditions with much more precision than with standard guages.
- Communication
Why use a cellphone if you can read email, or have it read to you? Why use a CB if you can IRC?
- Entertainment
This was the first thing most people I know thought about in terms of computerized cars: how can I play MP3s in my car? (and I say WarDriving is in this category)
I have two posts [1][2] on my Portal about this subject, and it seems that Detroit is looking into this issue, too. Technically, it's fairly easy to computerize your car. It's largely a UserInterface problem, really: how do you set it up so that you don't have all your users driving into trees?