The guys at 'Improv Everywhere' brought the movie Ghostbusters to life in the reading room of The New York Public Library at 42 Street. The 1984 movie begins with a scene in the very same room, so they figured it was time for the Ghostbusters to make an encore appearance.
The stunt is to raise awareness of the huge budget cuts at the The New York Public Library.
More info here: http://improveverywhere.com/2010/05/18/who-you-gonna-call/
Hilarious Ghostbusters Improv Video
on 1:40:00 AM