>I wonder what would happen if you disabled the GPS? Since GPS is passive, the police certainly wouldn't know if your cruised on by without paying.

You know, I've thought about it, and GPS is probably too complex for what this system needs to do, really. The car system just needs to periodically tell the government what your odometer value is whenever you gas up. If you try to gas up and the gas pump can't communicate with your car, or if you're buying too much gas for how little your odometer is reporting, authorities will be notified of the possible fraud.

That's still way too invasive for my tastes, though. In California, very little of the gas tax revenue actually goes to fixing the roads anyway... Most of it is wasted on less useful government programs. If they'd just spend the current gas tax revenue on the roads, as it is intended to be spent, California would probably have the nicest road system on the planet, and these intrusive new methods of taxation would not be necessary.