This is a remix of ‘Rotating Rings Toy’ by Marvin.  I love the rings toy, and really liked the feel and roll of the center ball, so I put 3 together to make this little fidget toy.

You can play with it however you like, roll the balls around your fingers, roll along your leg or various surfaces, spin it on itself, etc.  It's fun to fidget.

Update:  My wife could not put this one down, so I refined the design a little and left the curved edges for a nicer feel.  Black image is updated version.