Where can i find illusion pictures?

Question

i am looking for a websit where i can find pictures that trick your eyes. like the pictures you have to look at for a long time before you see the hidden picture. #1- what are these pictures really called?

#2 where can i find them online and maybe a book.

Answer 1

http://www.moillusions.com/

Updated almost daily with new illusions.

Or are you talking about stereograms, abstract pics that if u look at it a certain way, you'll see a 3d picture?

http://www.eyetricks.com/3dstereo.htm

Answer 2

Visual Phenomena or Optical Illusions.

Find them here: http://www.michaelbach.de/ot/