Mod DB is the largest website dedicated to supporting independent development of games

Modifikace is a Czech news and review site for single player Half-Life 1.

Mods Online is a news and community forum, with a very active user base.

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.

OzSource is the home of the Australian Gaming Combine. Steam discussion, Community Portal, Gaming news and opinions, critiques, retrospectives. Oz Source has been resurrected from its Half Life 2 Deathmatch origins.

PCosmos is a great list of Half-Life maps and mods. It is also available in French.

Planet Half-Life is the daddy of them all. It’s been online longer than most and is generally updated daily.

PlanetPhillip.com contains the most comprehensive database of single player maps and mods for the Half-Life series of game on the Internet.

Podcast 17 is a weekly verbal tour of the Half-Life community. It covers everything related to the Half-Life universe and features lively, informative recordings.

Scrama – The Art Of Level Design is the portfolio of Scrama; a level designer from Russia.

SLUM is Czech Steam community and fan portal about Steam and Valve games.

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.