A few decades ago, if someone wished to spend thousands of dollars on trainers , people might call them crazy. But today, sneakerheads have changed the worths of fashionable items and the very face of investments . Read on for a truly head-spinning mix of holy grail trainers sold for dizzying sums of money, ranked by price tag … 11. Nike MAG self-lacing Back to the Future II – US$104,000 The self-lacing Nike MAG is quite possibly the rarest and most desirable trainer ever made. Based on Marty McFly’s attire from Back To The Future II , these cool kicks…