Topic: Car navigation system
How about using the Chumby as a car navigation system. Use one USB port to store map information and application, the other for the GPS receiver (via Bluetooth, USB to serial to GPS receiver, or direct attached GPS receiver), port one of the open source navigations apps (like Roadnav, http://roadnav.sourceforge.net/index.php), finally the power, which could be taken care of by a cigarette adapter. I can see where the Chumby can sit nicely over the car dashboard :-)