This cube made of gears is a great example of some of the really brilliant stuff coming out of the 3D printing scene; it's a phenomenon on Thingiverse, where the method for turning any solid shape into a geared wonderment has been generalized into a formula that can be applied to your 3D model-file.
I write books. My latest is a YA science fiction novel called Homeland (it's the sequel to Little Brother). More books: Rapture of the Nerds (a novel, with Charlie Stross); With a Little Help (short stories); and The Great Big Beautiful Tomorrow (novella and nonfic). I speak all over the place and I tweet and tumble, too.