As you go down the page, there are a series of increasingly insightful and enjoyable examples. I particularly liked the animated random-dot autostereogram, the

As you go down the page, there are a series of increasingly insightful and enjoyable examples. I particularly liked the animated random-dot autostereogram, the one illustrating binocular rivalry (I had no idea there was a way to experience binocular rivalry without a stereoscope!) and the chessboard one (where even the pattern is 3D). Incidentally, I have poor eye accomodation (ability to change focus quickly), and so once I acquire the stereo perception of a stereogram, I can easily retain it for 10-15 seconds even if I close my eyes. On the flip side, it's been 10 minutes since I read that article and I still can't focus my eyes normally on the screen!