Here is a nifty visual effect that can be done all in camera and in real time without the need for 3d object modeling and any other computer use.
It's a tutorial on how to make books fly around in a room as if by themselves. There is even a video example provided on the same tutorial page.
This is a great effect that can be used in practically any haunted house/paranormal/demon flick. Hell, it can even be used in your own haunted house in time for the Halloween season, which is around the corner.