Hey there!
Today I made a fidget spinner like contraption =)
This is probably as close as I could get.

Similarities:
- Is carried arround (not a structure).
- Changes state.
- Slows down after a long time.

Differences:
- Doesn't rotate.
- Doesn't look like a fidget spinner.

Simply put a wool block in your offhand slot and watch it change colour!
You can give it another spin by re-inserting it in your offhand slot.
You can use "F" or a custom keybind to swap items from your hotbar to your offhand slot and back.
On the back of the structure, you can define which wool colour comes after which other colour.
You have to use sub-ids for this. (Press F3+H and then hover over an item, it's the number behind the slash.)

Look at the video if you want to see how it works.

Download as .nbt file (structure) is at the top right, the big yellow download button.


You can also use my installer to make the installation (of both types) easier!

Have fun!