Thanks JCL, that's a good suggestion. I've taken a look at a few itronix laptops -- they look like they'll do the job. I just need to find a way to do an auto power on/power off. Also, there may be some power concerns when leaving the laptop in hibernate mode. My guess is that the laptop would suck power out of the car battery to charge it's own battery. Maybe the solution is just to remove the laptop battery altogether.

I live in Toronto btw.