Yup, very similar to my ideas. I'm already along way down the road (groan) with another computer implementation specifically for info gathering in the car. It has a CANbus interface, and a heap of I/O and A/D. The intention is to look at suspension behaviour, manifold pressures, fuel delivery, etc. The car being "wired for sound" is a nice benefit, but it's not the only thing I'm interested in.

Being able to link them up was one of my first considerations; the car computer will be using USB hub capability to talk to empeg. Hugo's announcement of PPP over USB makes things seriously nice....