Michelin Tire company has an idea. Imagine how far your hybrid/plug-in would roll - if your tires could "get skinny" ... effectively reducing tread contact with the road, down to the size of bicycle tire. Is it possible? Michelin thinks so. They are working with Electroactive Polymers (EAP's) that can flex like your mussels flex when the brain sends electric signals out to them. Look at the center of the illustration and you'll note how the tread can be altered, turning on driver need . . . . wet roads, dry, snowy, low rolling resistance, etc: If Michelin makes this work ... your 50mpg ride could easily double its range. The drag from tire tread (or the lack thereof) can be a major factor on a vehicles mileage/range, turning on speed.