ok, I'm moving in this direction now. I just got an apple tv 2, which only needs 6 watts to run, and almost nothing to sleep. Converting it to DC -DC only now. I'm now switching the audio source and processing out of the computer and into the Apple TV box, with optical out to my processor.
I'll probably shrinkydink the computer down to a panda board, used only for controlling the car functions, via something like your software and the fusion brain.
I think I'll network the computers in the car with a modded wifi router, connect to my iphone for internet access for now, or have it run a bridge off any available network.
From your testing, do you think the panda board could run as an NAS device with an SSD for a drive, as well as running the FB6? I'm about to order one, I've gotta find something that can stay on 24/7.
Ideally I'd also like at least one camera served over the internet from the car, when connections are available. You should add webcam support / server to your software :)
Internet Controlled Car
I created a similar project during my undergrad. For detailed step by step instruction including all source code see; http://www.brandoncaddow-young.com/internetCar.php
Anyone still have a copy of the "microcontrolcenter-alpha1-source.zip" file? I've been interested in messing with this, but his site just displays the default apache page, archive doesn't have a backup of the file.