Twist one way and this toy turns shows a slow spiral pattern. Spin it the other way and you get a very different stairstepping pattern. It's all a matter of playing with angles of rotation. Thanks to parametric design and 3D printing it's a quick path from idea to reality.
OpenSCAD is a horribly ugly little program that can do wonderful things if you like thinking in arrays and loops. The process of learning it takes a couple hours, but it's free and worth the time. Here's a quick overview of how I got into it.
I'm a math geek so all of this appeals to me, but I understand if you're normal and don't want to do it. The print files are coming up soon, I promise.
OK, parametric folks, let's do this.