I like the idea. If only we had a system of cars, that for a small fee could drive us anywhere we wanted. That fee could be based on the number of kilometres travelled and the time spent in the car. We could call that fare a "taximeter", based on the latin "taxa" and the Greek "metron" meaning measure, together as "taxed metre", as that's a bit long - in time we could shorten it to "taxi".

Then we could have certain cities where only these "taxis" (and other kinds of public-transport) were allowed entry. Normal cars could enter, but would need to pay a special "congestion" fee.

Maybe London could try this out as they have a problem with congestion.