re: Magnetrons under the pavement?
A good question on energy. I don't know how much power is consumed by a toothbrush charging station if the brush isn't drawing power from it.
I could see such magnetrons being featured in parking lots in specially-marked spaces. Our local Fry's Electronics has a few normal electric car recharging spaces. Even if power wasn't an issue, you would probably want some kind of "handshaking" signal between a car and the space to start it up. I don't know what would happen to a pacemaker or something if someone walked across such a thing.
As for charging speed, the Tesla claims a complete charge in as little as 3.5 hours, and with a claimed range of 250 miles, that's pretty good.
