Team Fortress 2 is pretty great, but you know what would make it even better? Did you say “one or more zombies”? Yeah, us too. But instead, you’re getting a hat.

“For the first time in history, two separate Valve universes collide. That's right: it's a Left 4 Dead/Team Fortress crossover! This is not fan fiction! This is not a dream sequence! The characters from Team Fortress 2 will team-up with Bill's hat from Left 4 Dead 1!” reads a post on the TF2 Blog.

There’s a catch, though: Bill’s ridiculously regal Head Enhancement Item is only available to those who have preordered Left 4 Dead 2.
 
Honestly, though, to make such a strong fashion statement – nay, a fashion exclamation – we would’ve shelled out the full fifty smackeroos even if Left 4 Dead 2 weren’t involved at all.

Ok, not really, but you get the idea.