Acrobots

Articulated models are a staple of art classes around the world, but we've never seen any like these. Acrobots ($7-$13) are articulated, but feature magnets in their feet and hands making them stackable, more posable, and (obviously) attracted to metal. While they are great for models, they're also great to keep on your desk to play with — or torture — when you need to get your mind off work.