Car charging

In the recent budget the chancellor placed much more emphasis on the rates of car tax based on the pollution caused by the car. Since the resultant car tax disc is machine readable via a bar code, this introduces all sorts of novel applications, including:

1. Car lanes for the exclusive use of cars that don't guzzle gas (e.g. £100 car tax a year or less)

2. Preference car parking spaces in town centres for more environmentally friendly cars, you get into the preference section via a camera scanning your tax disc to raise a barrier.

3. Different toll rates on bridges. After all the damage to the bridge varies with the weight of the car, so smaller cars with lower tax values should pay a lower rate to use the bridge.

4. Cheaper meter rates for parking in towns for smaller cars to cut down on rush hour pollution. You register your number plate via a mobile, the computer looks up your tax code and the meter prints the ticket accordingly and includes your number plate on the parking ticket.


Any other potential uses?