I have been thinking along these lines for many years now, but I was not waving it around, because I thought @ some point I might be able to exploit the idea. As I have come to find out in the years following my initial idea to do this; it had already been done before!! Now, why it never took off and bacame a staple eluded me until now! Now, I see that the main hold up was not the principle of inductence itself, but the lack of a super capacitor and also I think the rare earth magnets contribute quite allot to the power output making it more of a possibility!
I saw an ad for a car set that was marketed by Heathkit in the 60's(?) that ran by inductance; my grasp of it was that they had a magnets or a coil or something in the base of the track and that charged the car as it passed over the top of it. The problem with their set was just the times, because the IC's and Digital/RC technology to control the steering and the throttle had not really been developed yet, So I am not 100% on how it worked exactly????
I watched a few of the video's there and it certainly looks like something you could really retro fit to the car!!???
I am sure Wes is all over this already!!