I think we're only thinking of the tip of the iceberg. Speeding tickets, monitoring highway use for tax billing are easy. Next we could see tax calculated on basis of number of persons per mile driven; or monitoring of fuel use and then calculation on number of people per miles X gallons. Limits on power/kg ratio for car use on roadways. In times of fuel scarcity, monitoring of driving so as to limit it to every other day or similar (think of watering lawns during droughts). Electronic registration checks, and biometric identification of drivers so as to allow checks of licenses and records. Installation of wireless monitoring of pre-start breath alcohol checks if one has a conviction of DWI, or perhaps if the vehicle has been parked near a pub during the last hour. Wireless control of starting/running engine based on whether registration is current. Ability to stop car's engine remotely by police. Location monitoring to enforce restraining orders, and then to ensure kids are dropped at school. Remote interior atmosphere sensors to prevent carbon monoxide poisoning, and then later to allow for remote airborne THC or other chemical testing. Use of vehicle electronics to remotely listen to/watch activity in the car. (You really think the NSA will stop at cell phones?! Oh, you n?ive creature!) But we will be constantly assured it's for our safety and well-being, indeed, even that we asked for all of it. And it'll be true that we did.