What's in the box?

This video shows a first-person perspective of some nameless, faceless guy running from a HAZMAT unit of some kind after acquiring a strange cube. It is amazing on its own, but if, as Kotaku says, it is a viral campaign for Half-Life, then it's even more worth watching. It sure has a lot of relations with HL, but I don't really think Valve is behind this. I hope I'm wrong.