Cumulative MPG display visible outside the Volt
I think it would be a great "awareness" idea to have a display visible from outside the vehicle (license plate area, one of the blacked out dash/decklid areas) that shows what the cumulative MPG is for the vehicle.
I was thinking something like:
Miles driven: 3,542
Gallons used: 12
Or, just leave the MPG off and let people figure it out. For those people that won't really need gas because of the length of their daily commute, this would really boost awareness of the volt's potential.
Not sure how simple that would be to work out without some owner input, though.