I'm on a real "analog" kick lately. Besides smoking tobacco pipes (mostly corncob) I've been training myself to use abacus for an hour a day. Mastered addition, almost have subtraction down to muscle memory, venturing into the world of division/multiplication next.

Rubiks Cube has been a staple office toy for me for quite a while. Way more fun than a fidget spinner. Abacus feels like a natural compliment..