Colour mixing online

Have a look at this if you are looking for some colour inspiration or a way to create, save and swap colour palettes:

http://kuler.adobe.com
You can register and save all your custom palettes to be used in Photoshop and Illustrator.
For example:
http://kuler.adobe.com/#themeID/75242
http://kuler.adobe.com/#themeID/106002

You are even able to make a palette from an image you upload or have loaded into Flickr
http://kuler.adobe.com/#create/fromanimage

Here is a video explaining briefly how to use Kuler

You can also have a look at ColourLovers for more colour and pattern palettes.
http://www.colourlovers.com