Meet the Engineer
Considering the name of the site, it seemed oddly appropriate to post this video. Everything you see is true to life: we engineers frequently sit and play guitar in the middle of battlefields, and we most definitely wear orange helmets at all times. If you haven't been following the amusing character profiles, you should also check out Meet the Heavy and Meet the Soldier. The cartoon-like visual style is really striking; I'm really hoping that the light-hearted approach translates into the actual game.
These videos are promos for Valve's Orange Box video game compilation, set to be released on October 10th. The set is a bargain, including Half-Life 2, Episodes 1 and 2, Team Fortress 2 and Portal for the price of one regular game. Furthermore, if you pre-order the game off Steam then you'll not only get into the TF2 beta, but also get Orange Box themed Peggle Extreme (pictured above)!
Update: Rock, Paper Shotgun has been doing a really great 9 part series detailing each class in TF2. If you're beta-less like me, this might help tide you over.