baroquedub

For website design and whatever… in no particular order:

Colour palette from an image file
http://jrm.cc/color-palette-generator/

Colour scheme from a single colour
http://www.colorschemer.com/online.html

Colour scheme from a single colour – uses basic sliders and includes an html/css preview
http://www.themaninblue.com/experiment/Technicolor/

Colour scheme from a single colour – Very intuitive sliders, exports Illustrator and .act (photoshop/fireworks) colour tables
http://colorblender.com/

Flash Colour wheel
http://www.sessions.edu/career_center/design_tools/color_calculator/

Nice community site for colour combos – includes a palette generator and ‘grab colours from a url’ utility
http://www.colorcombos.com/

“A directory of nice colours”
http://www.colorwhore.com/

Convert to and from RGB/Hex/CMYK
http://web.forret.com/tools/color.asp

Blend from two colours with up to 10 increments
http://meyerweb.com/eric/tools/color-blend/