EDIT: Customiser doesn't seem to work, so if you want to make your own you'll have to download OpenSCAD and edit it on your own computer. The way I've generated the curves takes a lot of computing power, but I haven't found another way to get the shape I want. Sorry! I'll keep working on a fix, and update when/if I have one.
If you haven't seen a fidget spinner before, then you're new here.
But this one uses only 3D printed parts, and is customisable! Change the thickness, diameter, number of arms, arm length, and curvyness (it's a technical term).
They can also be very tiny, so ideal for discrete fidgeting, or for small makers, mini-engineers, or pixies. The caps should press-fit together, or can be fixed with a small amount of superglue on the edge of the central peg, but be careful not to get any on the moving parts, or your spinner won't spin.
This was inspired, by, but not a direct remix of:
Try printing the caps with concentric fill on the bottom surface, they look more interesting that way. But remember to change back to standard linear fill for the main body of the spinner, or you might end up with gaps in them like I did for the tiny one-arm version.