Optical Illusions - M.C. Escher

I'm sure you guys had noticed the many pictures of optical illusions hanging on the staircase of the Science Centre. I find these optical illusions very intriguing and it really is a feat to be able to draw them. You can check out this URL http://www.mcescher.com/ to see the many works of M.C. Escher, whom I believe is the creator of this form of art.

Simply amazing!