Griffin CarTrip jacks your iPhone into your car computer - TiPb at CES 2011
Griffin's CarTrip is a tiny Bluetooth peripheral that plugs into the diagnostic port contained on most modern cars and transmits back usage data and error messages to an app on your iPhone. You can use this data to track different performance data over time to try and maximize your fuel efficiency, or just to pull off any problem reports so you know when -- and why! -- you need to go to a mechanic.
We got to take a look at it live from the CES 2011 show floor so check out the video up top and let us know whether you'll be getting one for your ride in the comments below!