The Economist reports that the British government has released its new transportation policy report: "Stop-Go"
"SHORT-TERM cowardice and long-term courage: that's Britain's transport policy in a nutshell, following a bunch of big announcements. This week the government gave its strongest commitment to road-pricing. By 2014, technology permitting, drivers will pay per mile driven, ranging from pennies on lightly used country roads to �1.30 a mile at peak-time on the most congested urban ones.
That scheme, requiring a meter in every vehicle, would cost an annual �3 billion to run, but would bring in revenues of up to �9 billion. The surplus could go to public transport, or be used to cut motoring taxes.
Either way, the scheme's welcome, if a long way off: rationing road-space by congestion is inefficient, dirty and expensive. In the nearer term, local authorities will be encouraged to adopt their own congestion charges, as pioneered successfully by Ken Livingstone, the mayor of London..."
As I think the proposal must be to put a combination GPS/radio unit in each car; these units would communicate the car's location to a satellite.