Playing billiards and having tons and tons of books. I also forgot to add chess in particular.

People can possess enormous collections of books, and do, but I really bet them that they don’t pick up to read a single one. Only to sometimes bring up certain lines to win online and pointless arguments over.

Billiards is usually a bar/pub kind of game, but some others seem to associate it with intelligence. You don’t need to be intelligent to play billiards.

Chess is self-explanatory. Lots of people throw around the line of “people are playing checkers while X plays chess” and other similarities. I think people look way too into chess as being a measurement of intelligence.