I hate to brag about an exclusive, but...

I found this notice hanging on at least two bulletin boards at the University of Missouri-Columbia's Engineering Building-East.  This photo was taken 3/24/2011.

Is this a fan-made teaser?  Perhaps, but why go to the trouble?  And why post it to multiple locations in the building?  On the other hand, if this is from Valve, why would they include their fax number and tell people to call it?  I am curious about how widespread these fliers are.  Has anyone else spotted one at their university?  My gut wants to say this is a teaser for a new Half-Life game, whether it's Half-Life 3, or Half-Life 2: Episode 3 (more likely of the two, in my opinion, although don't be surprised if it's longer than any of the previous episodic installments.  It would pretty much have to be after the wait fans have gone through). So, there you have it: confirmation of a new Half-Life game maybe!