Pittsburgh-based startup Shift Robotics has invented “shoes” that let you walk 250% faster without expending any extra energy — and you can own a pair of the speed-boosting kicks for $1,400. The experience is described as similar to walking on a moving sidewalk at an airport — you aren’t expending any extra effort, yet you’re traveling faster.  reserve a pair with a $50 refundable deposit, with the remaining balance expected once the company locks down a delivery date