Star Wars destroyer droids and Metroid morph balls might be beyond modern technology, but their basic trappings are within reach. Norwegian engineer Kåre Halvorsen built this robot sphere in his spare time, with six retractable, expanding legs that let it dance when it's not rolling. Well, technically, it doesn't roll quite yet, as the prototype's 25 servo motors haven't been programmed to do that, but Halvorsen says that's next. Then, we just need a few propellers, some hydraulic jumping legs and a smartphone app to control it, and we'll be in business.