I think the idea is great. One word WINAMP!!! in the car. Nothing in the car audio industry can beat that. With playlist, visual, etc. capabilities. I would think, just get a labtop with decent memory and hard drive, mount it under a seat or in the glovebox and hook up a custom mounted lcd in the dash and an ext mouse somewhere convenient. The only question I would have which I am about to look up in those MP3car.com threads, is how to get the power inverter to go on with the ignition. And would you have to manualy shut down windows and the comp everytime you turn off the ignition. Even so it would still be a simple way to just use for roadtrips and hangin around. It would be great for me because my car is out for my works (Curcuit City's) audio show every year, so it would be cool to just have on and play visuals with music, etc. Those are just my thoughts, most of you seem to know more than me. Good luck with the install bennyboy, post pics when its done. I'd like to see how it comes out.
