Even before Leonardo DaVinci came on the scene with his unique synthesis of scientific and aesthetic pursuits, artists were experimenting with sculptures that could move in various, mechanical ways. Today, with 3-D printing, mobile computing and advanced robotics coming into their own, machinery can routinely achieve feats that were utterly impossible in the days of DaVinci. Machine art in the 21st century is an exciting developing space, and it's already produced some really cool creations. Here's a look at five of the most amazing artworks made from machines (and a bonus sixth just for fun).