Eyes - mirrors of the world- Iluzii optice

http://kids.niehs.nih.gov/games/illusions/

http://www.optics4kids.org/home/content/illusions/

http://www.ritsumei.ac.jp/~akitaoka/index-e.html

http://kids.niehs.nih.gov/games/illusions/illusion_10.htm