I love optical illusions (see Related Posts at the bottom of this article for more), so I was happy to discover that every year, the Neural Correlate Society has a contest to find the best ones. This year's Top 10 finalists have been announced. My favorite (which I can't embed here, sorry) is called "Grouping by contrast". You'd swear the spots are not the same color, but I cut two holes out of a piece of paper to block the background, and sure enough they are. It's incredible. The illusion is a variation on the well-known chessboard contrast illusion and is similar to another illusion showing that how we see colors isn't as straight-forward as you might think. Another cool one is this:
[embed width="610"]http://www.youtube.com/watch?v=IjMVsTFVX10[/embed]
Click play, and stare at the white dot in the center. You can easily see the dots changing color... until the dots appear to rotate. ...
