SC2, if you fancy a game that combines, strategy, instant decision making, and gaming mechanics and reflexs
When I had taken my gpu miners down last November cause of poor payback, I converted one to a gaming machine and had purchased SC2. I played it a few times along with Borderlands 2 and Rage, but then the prices of bitcoins and the alt-coins went up and I put the gpu miners back online.
I still have the GPU miners running, but am getting close to shutting them down again. In the mean time, I have been playing Magic:The Gathering in real life and just recently started playing the online version, MTGO. What I found was that I can actually play it while still mining as the overhead from the game is low. The miner loses about 20KH/s while playing, which is not that much for a couple of hours of game play.
So, MTGO is the game I have been playing the past couple of weeks. Still getting my @ss handed back to me in match play, but I am getting better.
If I take the GPU miners offline again, I will be back to play some more SC2.
I used to play on my gaming desktop while mining, sc2 is not that of a heavy game at intensity 13 the games runs fine, but what I do now is play on my ultrabook while using my desktop monitor and gear, it plays fine, at good setting with few slowdowns when I have many tabs open on browsers and flash stuff (but might be ram related, as I only have 4gb on my laptop)