Valve has announced that if you pre-order Left 4 Dead 2 on PC you will gain access to Bill's hat in Team Fortress 2. "For the first time in history, two separate Valve universes collide.

Valve has announced that hat-hungry Team Fortress 2 ... code can now don this fall's hottest TF2 fashion accessory--the green beret made famous by Bill in Left 4 Dead. "And lest you think this ...

You can check out the post in full here. I for one, had no idea that the hat took it's initial cues from the image on a TF2 noisemaker, and it's neat to see an early iteration of the hat ...

it was also revealed that Oculus Rift owners would get a unique TF2 hat (a popular in-game item type). Today the TF2 Oculus Rift hat is officially redeemable by those who were part of the Oculus ...