1. Battlefield 2142: is a first person shooter designed by DICE and is the fourth game in the Battlefield series. Titan mode gameplay is extremely fun and gives plenty of meaning to the mindless shoot em up style game.
BF 2142 is playable only after a somewhat complicated installation and configuration.
2. Counter-Strike: Source This game needs no introduction. It has been kicking ass and taking names since 2004. With so many modifications to CS:S, you will never get bored. I’ve been having a blast playing Zombie Mod which pits both Terrorists and CTs alike against Zombies with knives… get knived, turn into a zombie.
CS:S is playable after moderate configuration.
3. Day of Defeat: Source This is just one of those games that just seems to have tons of players on at any time of day or night. Very popular, extremely playable using Wine.
Not much is needed here to get things working properly.
4. Enemy Territory: Quake Wars iD software is releasing a linux native version of this game. I’ve played the beta for several hours and came away impressed. I’d venture to say the game is a Battlefield-style shooter with plenty of vehicles and being able to play as a Strogg is definitely refreshing for a change.
Although it’s not quite 100% true to form, it would be best to get the linux native client.
5. Garry’s Mod Who? Garry. This game runs very well with a few quirks (intermittent slowdowns), installs right from Steam with no issues. Very playable. Mods even work just fine!