[Doug Heffron] modified this 1989 Geo Metro way back in 1993. Gas prices had just started breaking $1.00/gallon and he wanted to show manufacturers how to build a fuel efficient vehicle in such troubling times. The car already got 58mpg (Prius: 46mpg), but [Doug] decided he could do better with some aero modifications. The car was converted to tandem seating and stripped of any extra weight. In its final form, it got 75mpg, but then gas prices stabilized and it was laid to rest in a shed. You can find out more about the car and see photos from the build on its site (painful resizing).

[via Autoblog]

[dcb] posted about his work on the mpgduino mpguino. The project uses an arduino with a LCD display to monitor fuel consumption based on vehicle speed and the pulses of the fuel injectors being fired. It’s definitely an interesting project given current fuel costs and the passive nature of the project. You can easily tap the wires needed for the monitor and remove it without voiding your warranty (not that we really care).