Let's not call shoes we like "rationalist shoes".
Edit: (Original title of the post was "Rationalist Video Game: Frozen Synapse".)
I think it has a deeper connection than being "a game rationalists like": it seems like an actual game where you can practice conditioning on the other player's decision theory, because, IIUC, you learn the various ways they would respond to various choices you make. And conditioning on another's subjunctive output is a crucial element of the Newcomblike decision theory problems we talk about here, and discussed mainly in that context.
Disregarding for the moment the question of whether video games are a rational use of one's time:
Frozen Synapse is a turn based strategy combat game that appears to be particularly interesting from a rationalist standpoint. I haven't played it, but according to the reviews, it's actually a combination of turn-based and real-time play. Each turn encompasses 5 seconds of realtime, but that 5 seconds of realtime doesn't happen until both players have constructed their moves, which they may take as long as they'd like to do. Constructing a move involves giving your several units and your opponent's several units commands, watching what happens when the units play out those commands, and repeating that process until one has a set of commands for one's units that one considers optimal given what one predicts one's opponent will do. This happens on a procedurally-generated battlefield; there are reports of this occasionally giving one player or the other an insurmountable advantage, but the reviews seem to indicate that being able to play on a fresh field each time and having to think about proper use of its layout on the fly outweighs this issue.
Also, the game came to my attention because there's a Humble Bundle available for it now, which means that it can be acquired very nearly for free; just ignore the 'beat the average to get more games' hook.