This collection of seven videos were shown at the Leipzig Games Convention. It includes an awesome trailer from 
Team Fortress 2 outlining the different classes, a Portal trailer showing some more gameplay and 5 different 
movies of Episode 2 footage. Check them all out in this big bundle!

http://www.fileplanet.com/166938/160000/fileinfo/Half-Life-2:-Episode-Two---Leipzig-Movies

gc2006_portal_play.mpg - http://www.4gamer.net/games/033/G003379/20060827171726/