Yesterday, a teaser trailer for The Last of Us burst on to the scene and really didn't tell us much about the game. Today, we know the PlayStation 3 exclusive is about brain fungus. Maybe. The Last of Us teaser trailer features riot and disaster footage with a voiceover longing for the simple things we take for granted. Sounds like a post-apocalyptic game to us. What could bring about the end of the world? Brain fungus...