If you're not a subscriber to FreddieW's YouTube channel, you should do so if you love video games. He's put out some great little videos paying homage to various video games. Freddie and his partner Brandon paid a visit to E3 2011 and they ran into the booth for Half-Life 2 Episode 3, which had a really short line. Man, how did I miss it when I was there?
Of course, if you know Freddie and Brandon, they specialize in SFX YouTube videos and no, Valve was not showing Half-Life 2 Episode 3 before anyone asks.