Most people can't grasp RGB, CMYK, & HEX. This color picker is for them.
http://33cc77.com/tools/colorplane
jQuery (but you can easily edit it to use another library)
Colorplane was created for Green Room, a private group chat tool we built to share with our friends. Instead of avatars, users are represented only by a color. green.33cc77.com Green Room signup page
Writers on Svbtle choose a color to represent their profile. In the past, writers had only a text field where they could input a HEX code. Now the writers can use a Colorplane to find just the right color. svbtle.com Svbtle settings page
Inspiration from Hailpixel