GM, Michelin working on puncture-proof tire
[gtxvideo vid='LPIPxjuv' thumb='http://player.gtxcel.com/thumbs/LPIPxjuv.jpg' vtitle='GM, Michelin working on puncture-proof tire'] (CNN) - General Motors and Michelin are teaming up to create an airless, puncture proof tire. The prototype "Uptis" has treads in the middle and no side walls. GM says it's…