Professor Michael Bach is certainly one of the two Internet kings of optical illusion. Here is one of the latest and most delightful illusions to appear on his website. Just click on the image of the two blurred faces above to go to it. If you have the latest (Fall 2005) Flash player you will see two human faces that cycle from sharp to blurred and back again. During the cycle, two amazing things happen: the faces drastically change expression, and they change sex! You'll need to see it to believe it. For a discussion and other examples, click here.

And here's a more recent version from New Scientist, April 2007, which you can see right here. Move your head close to the screen and inspect the photo of Albert Einstein. Now move your head some distance back from the screen, or keep your head fixed and just squint your eyes slightly, and see Albert transform into another iconic 1950s figure, Marilyn Monroe!!

The other Internet Maestro of Illusion is of course Professor Akiyoshi Kitaoka. Here's an example of his I had not seen before. The concentric circles composed of slanted squares appear very strongly to spiral.  Also, if you use your mouse wheel or the control on the right side of the browser window to scroll the image up and down,  you will  see the spiral in impressive illusory motion.  Finally, click on the image to see some of Kitaoka's latest works (December 2005).

To tide you over, if you can't get enough internet illusion pages, check out the new illusions created by Gianni Sarcone and Marie-Jo Waeber, here. Or try this heavy-handed parody of the typical internet optical illusion page.

A fond tip of the Stetson hat to:

Edward Adelson

Michael Bach

Akiyoshi Kitaoka

Alexander Logvinenko

Beau Lotto and Dale Purves