The New York Times has a cool article about gadgets under $200 that can be hooked up to the OBD II port of your car. The displays provide efficiency readouts or notify you if you’re speeding.
The ScanGauge II is particularly cool, because it will tell you how many miles per gallon you’re getting based on your driving behavior.
It reminds me of the information I saw on the in-dash LCD of my friend’s Prius hybrid—or the display readouts from when I played inside one of those BattleTech pods at Virtual World.
One day…
These Backseat Drivers Are Moving Up Front [New York Times via Digg]