I'd prefer not to suppress ideas, mcrews. There's always a chance that not all variables have been exhausted. I'm currently searching as per your request and I still see options.
racerc2000: I had thought about motorcycles as well, but the problem I find right from the start is finding a rim that 1) a cycle tire can fit on that 2) also fits on my car. Considering I thought about buying a $1500 set of snow tires from Canada, I'd be interested in knowing how much the cost of your idea would compare, too.
My thoughts on mini-spare tires is that they're too soft - it's one reason I thought that maybe by filling it with "something", it would improve performance. Think train wheels.
