Fun Optical Illusions Website
Someone on the Living Math email list forwarded a link to Shapirolab.net, a fun website focusing on optical illusions and patterns. Lots of information about why the illusions work and many have options where you can play around and change the illusion to test different effects.
This came at a perfect time as it ties in with a fun Brain Awareness program that Jason did a couple of weeks ago at the National Museum of Health and Medicine Armed Forces Institute of Pathology (at Walter Reed). One of the aspects of the brain that had been covered was optical illusions so this is perfect (I love when that happens!)