The L4D Map Database is a library of all Left 4 Dead maps (official and custom) in the form of a wiki that anyone can contribute to. Includes downloads, screenshots, videos, information, and more for each map.

L4DMods.com covers everything, and I mean everything, related to the L4D community.

Mine-Dog.net is an established group of gamers who enjoy playing all steam games together (and some non-steam games as well). They also enjoy making comics, movies, and all other forums of media. They currently run three servers that change games monthly. All are welcome to join. Previous Design:

Netday is dedicated to custom maps of high quality only. Maps are added regularly (at least one per week). It also covers mods like Dystopia, Portal Prelude and JailBreak. The map reviews are both in English and in French. It is advert free and features direct download to all files.

Obsidian Conflict is a co-operative modification created for Half-Life 2. It is a community based mod with focus on fun, co-operative and physics-related puzzles. The mod has an open story, but is still set in the Half-Life 2 universe.

OnlineGame.se is a Scandinavian site that covers Team Fortress 2.

Pájaros de Barro is a Spanish Gaming Community which offers public servers and support (tutorials, videos, forums, articles…) for Team Fortress 2 and Left 4 Dead as well as updated and fully spanish translated news and interviews related to Steam and Source Engine based games.

Phenomena On Break is a community brought together by their love of Valve games and games in general. They have used Valve games for over a year to make over one hundred comics based in the Half-Life universe, as well as the use the Source Engine and Gmod to create original universes and characters. They [...]

Sammy Servers lists servers to play Zombie Master and a few other mods and games.

SourceForts is a Half Life 2: Deathmatch mod where Combine and Rebels face off in capture-the-flag action with a big twist.

Steambans.com is a global banlist/watchlist made for the Steam technology from Valve. All bans that are accepted will enter a database which then is used to protect all servers under their supervision.

Steam Friends covers all the news related to Steam and Valve.