MindCuber Lego Minstorms EV3 Cube Solver
I built this in a couple of hours, and it's a joy to watch. It's quite humbling to be beaten by a robot solving a Rubik's Cube. All you need is this MindStorms EV3 kit (my Amazon affiliate link)
Ready for something even faster, check out the monstrous CubeStormer 2 on YouTube. And more recently the CubeStormer 3 on WikiPedia.
What do you think? Have you invested in Lego for you and your family yet?