I attended Ann Arbor Mini Maker Faire last weekend and was quite impressed by Ford's OpenXC project: "an API to your car". I'd read about project earlier this year but talking to the Ford engineers helped me understand the potential:
The current prototype uses a PIC32-based board with the to provide a full solution for listening to the CAN bus in the vehicle via the ODB-II port. The real power of OpenXC comes when an Android device is connected via USB. This allows Android apps to read many different signals in real-time as this demo shows:
One of the Ford engineers also showed me an interesting app which highlights instances where one's driving behavior has a negative impact on gas mileage. The idea is that reviewing this data would allow one to optimize their driving habits.
I also saw their latest prototype which uses the ARM Cortex-M3 along with a Microchip CAN transceiver:
Another prototype on display was this solar-powered heads-up display unit which can indicate system status and events via 5 LEDs reflecting on the windshield:
The OpenXC team will also be at Maker Faire Detroit at the end of July, so I look forward to catching up with them again there.