Marty McFly's self-lacing Nikes in Back to the Future Part II inspired a scientist who has developed filaments that harvest and store the sun's energy -- and can be woven into textiles. The breakthrough would essentially turn jackets and other clothing into wearable, solar-powered batteries that never need to be plugged in. There are a host of other potential uses, including electric cars that could generate and store energy whenever they're in the sun.