Humans have a predisposed fascination to risk. Games allow the simulation of risk in various situations such as FPS combat, car racing, etc. Also games are very good for working out your reflexes and your mind with the right type of software. When though through completely a game of BF2 really does test your reflexes as well as strategy skills, and not to mention your paticence too. Add in the teamwork component, and you have one brain exhausting of a game. I do think though that RTSs are the king of brain games, because it adds resource management economics. However I could argue the idea of economics in ammunition in BF2.......................but I won't get into that. I think it all really just comes down to satisfaction in some form, be it shooting a guy in the head thanks to your superior strategy or with the previously mentioned Hot Shots Golf, sinking that Birdie thanks to your working through predicting the ball's initial impact with the ground at a certain angle, rolling motion, etc.