After Counter-Strike 1.6 and Half-Life 1, another important game is now available in Steam for Linux: Counter-Strike: Source (CS: S), a popular first-person shooter developed by Valve.
Counter-Strike: Source is a remake of the original Counter-Strike, using the Source game engine, in which the gameplay is basically the same as in the original Counter Strike: the counter-terrorists team plays agains the terrorists in a series of rounds.
|Counter Strike: Source|
Since both Counter-Strike: Source and Team Fortress 2 use the Source engine, it is likely to see more games using this engine available on Linux, like Half-Life 2 and others.
For now, Counter Strike: Source doesn't show up when selecting Linux for the OS in Steam, but the game is available and can be played on Linux - simply don't select Linux for the OS when searching for it.
There's no news on Counter-Strike Global Offensive (CS:GO), the game released in 2012, but considering the rate at which Valve is making their games available on Steam for Linux, it shouldn't be too long until CS:GO will be available for Linux users.
Along with Counter Strike: Source, Valve has made some other games available for Linux recently: Closure, Psychonauts and Shank 2 (this one doesn't seem to work right now, according to SteamDB, it's missing the executable), but just like CS: S, they don't show up in Steam for Linux if you restrict the search to Linux.