Is it an aftermarket navigation unit?
Actually what I plan to do is to have a head unit which can have a video output like a VCD unit connected. I wanted the CD changer but that would mean giving up space for the changer at the rear of the car unless you can think of another place to place it. Big luggage.... ouch! Don't wanna smash the little thing.
So the plan is to have a VCD/MP3/CD-R all in one unit. DVD is too expensive at the moment.
There is a hard disk option like the sony unit, I wonder if any of them can play mpeg movies. Now that would be cool. Just download the movie and play!!!

Thanks

Ameet