http://www-ai.ijs.si/eliza/eliza.html

This is a fun site that models artificial intelligence and non-directive therapy.

http://www.psych.purdue.edu/~coglab/

This site provides an introduction to cognitive psychology through demonstrations

and on-line experiments.

http://web.psych.ualberta.ca/~mike/Pearl_Street/Dictionary/entries.html

This site is an on-line searchable dictionary that contains numerous terms used in cognitive psychology.

http://www.illusionworks.com/

Many auditory and visual illusions are presented that highlight some of the aspects of perception and its limits.

http://kahuna.psych.uiuc.edu/ipl/

On-line experiments in memory, learning, cognition, and perception are presented along with information about the purpose and the underlying phenomenon in each experiment.

http://valley.uml.edu/psychology/illusion.html

About 20 visual illusions are provided along with information on why they occur.