This website hosts numerous, heavily illustrated articles on the way that the brain and sensory organs function together. It also has interactive exercises to emphasize these relations.
The Exploratorium website hosts a number of interactive online exhibits focused on optical illusions and the way they relate to the ways we perceive things visually.
This is the self described “most comprehensive collection of optical and sensory illusions on the world wide web.”
Laboratory for Scientific Visual
This website for Virginia Tech’s Lab for Scientific Visual Analysis hosts information on linking research and education. It is primarily for use by Virginia Tech faculty and students.