8 Mind-Blowing Optical Illusions (video)
A.Kitaoka's Latest Works--Optical Illusions (check out the spirals!)
Optical Illusions and Visual Phenomena
The Sydney Opera House Illusion
Julian Beever's Sidewalk creations
http://www.youtube.com/watch?v=hfn8Dz_13Ms
http://www.flickr.com/photos/pavementpicasso/sets/
DON'T WORK: The following require the Flash plugin:
Color blindness in visual periphery
SF Exploratorium online sensation & perception exhibits
Senses and Sensitivity: Neuronal Alliances for Sight and Sound
http://www.defense-update.com/products/l/LRAD.htm
http://science.howstuffworks.com/lrad.htm/printable
http://schizophonia.com/archives/traumaArchive/psych/Barry_Manilow.pdf
http://www.compoundsecurity.co.uk/
http://jeffmilner.com/backmasking.htm
Half-Life 2 zombie sounds revealed backwards
Pharrell Williams has synethesia