Hmm. The first thought that comes to mind for me is one of those spinning rings. I got a set of 4 from Amazon that are black and I have one on my left index finger and spin it with my thumb.
Pretty sure I was spinning it for about 2 hours straight yesterday while I was working. It was just one of those days.
These are the ones I got, but there are many out there. I guessed my ring size the first time and got it wrong and had to order them again with the right size (adhd tax be like…), so learn from my mistake haha.