This is a very popular link these days, but my God! you can’t help but be impressed by these illusions. Stare at them for a little bit and you will get a headache. Stare at them for five minutes, and blood will start squirting out of your eyeballs. Or, as psychology professor Akiyoshi Kitaoka says on his illusions page:
Caution: This page contains some works of “anomalous motion illusion”, which might make sensitive observers dizzy or sick. Should you feel dizzy, you had better leave this page immediately.
He knows what he’s talking about. I nearly emptied out a conference room this morning by projecting these on the screen. On this page he has the explicit warning: “Caution!! The figure shown below might made you feel sick.” But really, nothing can compare with this one… make someone look at it for a full minute on a dare: Koma. Powerful stuff. Here are his latest works.