Carrom game boards. The American variant of the game with plastic rings. I bought one, then almost immediately another in a slightly different style. I'm planning my first fine woodworking project which will be a carrom board and I'm going to 3d print my own rings.
I played Carrom once in-country on a business trip once. It's an amazingly fast, simple, and incredibly hard game. I had no idea there was an American version!