I'm semi-active on ootpdevelopments.com/board, which is a forum dedicated to a micromanagement-intensive baseball simulation (kind of like Football Manager, only for baseball, and because it's for baseball it's a bit more stat-heavy and pays a bit more attention to the history of the game than FM). Lately I've been mostly posting in their hidden politics forum because I know a few of the people there and a couple others are batshit insane, but I also post quite a bit on the regular boards themselves when I get the inkling to because I know my way around the... man, I hesitate to even call it a game, even though you can definitely play it like a game. It's more like a tool to simulate fake baseball seasons for fun and profit.
Otherwise, does reddit count? Because that's the main other place, I guess. Oh, and a third small bulletin board that is mostly dedicated to one OOTP league, which has a person on it who I think I ran out of the SGUF because I post here too much and am annoying.