Valve have created Expiration Date, a 15 minute animated short featuring all the Team Fortress characters.
Source Filmmaker - Valve Favorites
Valve are showcasing some of the best short animations created with their new Source Filmmaker software.
Portal 2 - Authoring Tools Open Beta
The universally acclaimed Portal 2 is getting a level editor. Valve has launched an open beta for the game's authoring tools.
Portal 2: Lab Rat - Part Two
Read the second part of Portal 2: Lab Rat, the comic released by Valve as a tie-in into the new game in the series.