The above photos are a cheap finger mouse I bought a couple of years ago.
Top pic is how it’s supposed to be worn, bottom is how I now use it.
I didn’t really like using it as it was a bit crap, but that was until I fixed it to my throttle with some tape.
Now I have my fingers resting just above left and right mouse buttons, and a roller ball and scroll button just below those.
I also have PointCTRL but can’t use it properly at the moment due to needing blinds in my sim room. Whilst I really like it, I’m not massively missing it now I have this.