Adobe Kuler for colour ideas and cool colour functions in Adobe Illustrator CS3
If you are looking for design ideas for colour schemes, check out Kuler (http://kuler.adobe.com). This is a site set up by Adobe which allows users to post colour schemes, and there's some great stuff there.
Also, if you're an Adobe Illustrator user, check out this video on illustrator cs3 - there's some pretty amazing stuff you can do with colours...