I still think fuel duty is the best way of doing it. That follows the "polluter pays" principle, which is what you want. Compare 100 miles in a two-axle SUV and 100 miles in a Toyota Prius: the truck will be using around five times the fuel, and hence five times the pollution.

This isn't really the "end" of anything. The major problem they're talking about is people overusing certain key points in the road network - we're not talking that price per mile for an entire trip. Get people to travel some other way, or charge for travelling the direct way, and it'll share the load out. Remember that the M6 toll road has worked very well.

The major problem is getting into the US long-commute mindset. When Cambridge is being touted as within commuting distance of London, you know things are going a bit too far.

I'm not convinced about how it'll work technically though. A GPS box on every car - that's too open to abuse.

Graham.