Are those fans going to have access to the outside world? Problem with fans is that they require the ambient temperature to be cool enough, otherwise they don't do crap for you.
Just like you don't roll down the windows when it's 110*F outside....same principles of thermodynamics at work as a convection oven uses.
I've heard of comps in the trunk, usually as MP3 players....but beware, railroad tracks and other bumps don't treat hard drives very kindly, be prepared to replace the HD.
I'd have to agree about white getting dirty all the time, it's hard to keep clean. But it looks sweet.
b