I like this car more now that I've driven about 2000 miles. I've figured out that driving 55mph saves 15% more gas(that's 40cents/gal). It may enrage other drivers but on top of the high mileage with this car, it makes sense to drive 55. Have gotten a few key gouges on my car. I don't think people like the special treatment hybrid owners get.
Double the gas mileage with regular gas, not premium gas. Driving 55mph on the freeway gives 15% boost in MPG. In all, this car costs about 25% the price of a high performance car to operate, just in gas. Add regenerative breaking which saves on the break system: pads, rotors, calipers etc.
Add solar panels, extra batteries, natural gas option, 110V/60hz recharge plug-in, lithium ion battery option...in short, make it more fuel efficient.