ColorSchemer is a colour-picker. A widget enables you to grab Hex, RGB, CMYK and HSB values of any colour on your monitor image. The free downloads are : Galleria Widget for MACs and ColorPix for PCs. You can also browse colour schemes on the site.
The web-based ColorSchemeDesigner is an entertaining tool for devising colour schemes. Its colour wheel automatically genrates mono,complement, triad, tetrad, analogic and accented schemes. Then you can adjust hues and contrast and select RGB, Web or Opaltone colour space options.