But also to be 'fair' the Prius does NOT wear the road out as fast as the Hummer. Based on gas tax, the Hummer will pay a lot more per mile traveled. The 'mileage traveled' tax hits the guy who is doing what the administration says they want - but really don't. So raise the gas tax and I'll do my best to avoid it. Privatize the whole mess. They couldn't do worse than the government. The USPS come closest to being good - and they only lost 15 BILLION last year.