Telltale Games has something very interesting up their sleeve.  The trailer below is short and gives what appears to be a silhouetted image of Tycho from Penny Arcade, Sam from Sam & Max, The Heavy from Team Fortress 2, and Strong Bad from Homestar Runner.  No other information is given other than a date of 9/2/10, one day before PAX.

Curiouser and curiouser...