HL2World.com is a news and forum based site that has been around for a long time. The forum is particularly active.

Interlopers has been online since 2004. It posts selected Steam game news but its focus is on content creation.

Jailbreak is simple: Two teams, two jails. When you kill a member of the opposite team, they respawn, locked up inside your jail. Lose, and you get executed! Your objective is to imprison every member of the enemy team. The twist is, you can break out members of your own team, by fighting your way [...]

L4D.es is a website and Spanish Community dedicated to Left 4 Dead. Pagina web de Left 4 Dead en Español.

L4D Inside is a Russian L4D portal.

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.

L4D Maps is a website completely dedicated to Left 4 Dead and everything about it.

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

LanManiaX2 is a map and mod resource. But don’t let that simple description fool you, it contains a wealth of news and information.

Leak Free is a Source engine development community started in 2004, which consists of useful tutorials and a helpful community to answer all of your level design, modeling, and programming questions. One of the most noted features is the Valve Hammer Editor Error Listing, which describes all the errors in the software and how you [...]

Left 4 Dead 411 looks like the perfect place to start if you are new to the game. It contains plenty of help for new players.

Lit Fuse Films is a group of amateur film makers, some of whom use Half-Life 2 to create short films.