It looks like Robert Pattinson and Ashley Greene will be appearing (separately) on upcoming episodes of Jimmy Kimmel Live to promte their upcoming films (Cosmopolis and The Apparition, respectively).  The guests have not yet been listed on the official ticketing website, but for now it looks like their MIGHT be tickets left to the Rob appearance.

Ashley Greene, August 20

Robert Pattinson, August 22

Source via RPLife