Other
Color Matters: Vision: What Is Color Blindness?
Learn about the different types of color blindness and see a few simple tests that are used to diagnose this condition.
Biology Pages
Kimball's Biology Pages: The Human Eye
Written by a former author of Biology textbooks, this page describes not only color vision, but the anatomy of the eye, and color blindness. Easy to understand language.
Wikimedia
Wikipedia: Color Blindness
This site from the Encyclopedia Wikipedia provides information on the condition of color blindness, including different types of color deficiencies, a discussion on the causes of color blindnes, images, and more.
Other
Well styled.com: Webdesigner Tools: Color Scheme Generator
A totally cool concept! Choose your base color, your scheme (monochromatic, etc.) and the computer will show you what other colors go with it! There are even settings for various levels of color-blindness. A really cool art tool!!
Other
The Vision Learning Center: Color Blindness
Page with facts about color blindness. Provides good questions and good feedback about this eye condition and what treatments are available.