Augmented reality can make you see things that are not there

Brilliant installation by Lynx (Axe in many countries): A giant screen at London’s Victoria train station showed a live video stream of passersby. Embedded in it were the “fallen angels” from the marketing campaign. People were able to somewhat interact with them. Picture and link to video after the break.
The angel shown on the screen is added live into the picture.

This could also be used to really scare people, because of our fear of things that exist, but that we cannot perceive. Think of vampires disappearing in a mirror or the aliens in the movie “They Live” [amazon.com, itunes.com] that can only be seen with special glasses.