Valve have announced the Source Filmmaker, their tool for creating animated films in a very intuitive way.
Valve have created Expiration Date, a 15 minute animated short featuring all the Team Fortress characters.
Half-Life: Raise the Bar
Half-Life: Raise the Bar is a fan-made short film inspired by the Half-Life franchise.
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.