iPad for the car

I'd like to see a case for the iPad that velcros on (or similar) so it can be attached and detached from the headrest in front.  Alternatively, some sort of snap-in system where it goes in a bracket with cords hidden away for power (and maybe audio).  At $500, it's not much more expensive than other high quality 9" screens but it also holds a lot of media, is easy for the kids to run, and, obviously, is very portable compared to most screens.