Starcraft/Broodwar - Remains my favorite game off all time. Best balance between races, and very high-paced. Also one of the easiest games to modify I've played (mapping/modding). Very challenging and fun, and can be found for 10 dollars...will run flawlessly on a pentium 2...highly recomended (GO BUY IT)
Counter-Strike 1.6/Source - Most played game at the moment, get's boring though. Too easy
COD4 - Great game, I enjoyed the single player campaign, but I prefer the feel of Counter-strike for competitive multiplayer play
Crysis - Just plain pretty. A little bit short in campaign mode but there are engless possibilities, and a very open environment. My favorite game in terms of technology and prettiness.
Microsoft FSX - Some people hate them, but I like flight simulators...not just combat ones. I play this to just relax, when I don't feel like shooting things.
Battlefield 2/Special Forces - Good team-based game, and the maps are massive allowing for countless stratigies. I haven't played it much lately because it is rather boring to play alone, even online.
Poker - When I'm bored and have some money to burn I load up Pokerstars or Full Tilt Poker, and see how quickly I can lose it all (not the goal, but that's usually how it ends up).
Solitare
