Simple yet complex puzzle, inspired by the game The Witness. You can use it to store something inside, and it takes a total of 7 moves to fully unlock it. Watch the video to see it in action.
I'm putting this in my shop by popular demand, but I have to add a disclaimer since it's not perfectly smooth the first time you get it. There might be a lot of friction the first time you try to rotate it, so be very gentle until all the dust (from the 3D printing process) has fallen off. Do not force it. After a while playing with it, it should rotate pretty smoothly, just be careful and have fun!