Nano fidget spinner

I wanted a tiny fidget spinner as a novelty. Scaling down existing ones makes the bearings fuse together, so I decided to make my own. I'm pretty happy with the shape of the spinner and the simplicity of the code that generates it. As is usual for 3D-printed sleeve bearings, they'll perform better with a bit of lithium grease (and they will never perform as well as a real metal ball bearing).