Again great work, too bad you can't mass produce them but I understand. Since the Arduino was mentioned, I'll bring up the Raspberry Pi, are you familiar with that one? It's only $35 and has decent specs (1g ddr3, quad core) and a 40 pin gpio but no analog inputs, though add on boards are pretty easy. I've been thinking of ways to use one more for the unique factor than actual practicality. The most I've used mine for so far is a retro gaming station and media center but a stand alone car entertainment system isn't difficult which isn't really using it to its potential so adding more functionality like cruise and things like sensor management or really anything can be done.
