Wiimote + Car = good idea. Easy way to add buttons. Can turn a non-touch-screen in to a light-pen tablet (http://www.cs.cmu.edu/~johnny/projects/wii/ 2nd video down). You can also control the cursor using the nun-chuck joystick. The IR cursor method (install an IR LED above your screen) works great for passengers. The only thing that is useless is the motion sensor. I'm hoping someone makes an app that lets you see the cars G-forces due to acceleration and turning. That would be awesome.
I think its a cool idea also.... but from what it looks like, it has to be near the screen. While researching on touch pads, I came across this http://cgi.ebay.com/ws/eBayISAPI.dll...MEWN:IT&ih=019. Originally I was going to buy 6 touch pads, one for each passenger. Now I bought 2 of these, one for the 2nd row seats and one for the 3rd row. The 1st row can simply use the touch screen at the front. Only thing im worried about is if the devices use the same frequency or does each unit have its own unique signal.
Nirwana Project, the Android/Win 7 hybrid system!
1X Ainol Novo Flame Tab
3x Perixx Touchpads
3x 7 inch Screens
1X 7 inch motorized Screen
1x Win 7 PC