Valve have announced the Source Filmmaker, their tool for creating animated films in a very intuitive way.
Team Fortress 2 - Mann vs. Machine
A robot faction is introduced into the Team Fortress 2 equation, via this amazing new trailer by Valve.
Dota 2 - Cinematic Trailer
Valve have released an action packed cinematic trailer for their new game, Dota 2.
Zachariah Scott created a touching and haunting animated short called Bad Medicine, using Source Filmmaker.