Fidget Spinner

Prints flat (use auto place). I've remarked that 18mm circle diameter (not included, change params in fusion) yields a very spinny fidget. Adding a little grease should make it spinnier.  Additionally using random seams should make it more suitable for spinning.

After you take it off the print bed, hold the stem and triangle with your fingers to release the circle -- some back-and forth motion should be enough but be careful to not twist the stem.