Agave (formerly GNOME Colorscheme) is a simple GNOME utility for generating colour schemes.
Select a base colour and Agave will suggest a small set of colours which complement it. You can choose from several types of colour scheme; for example, selecting ‘Monochrome’ results in a scheme of different shades of the same colour, whereas ‘Complements’ just gives two colours which complement each other. If the scheme Agave suggests isn’t ideal, you can increase and decrease both the brightness and saturation of the scheme as a whole using the buttons on the toolbar.
You can select any colour on the screen as a base colour by using the ‘dropper’ tool (hidden away in the colour picker dialog). Three different representations of the colours in your colour scheme are given: Hex, RGB, and HSV, and copying the colours into a graphics application is simply a matter of dragging-and-dropping them. If you design websites and edit CSS, Agave may come in useful - particularly when your imagination fails you. The random button generates a random colour scheme, and repeatedly pressing it soon results in a usable combination of colours for you to use.
A small irritation is the limited number of colours allowed per colour scheme. While 2-3 colours may be fine when decorating a room, websites and graphics projects often require several more. Apart from this, Agave appears to have no major bugs, and most of the issues filed in its bug tracker are feature requests. There are several translations available, too. KColorEdit (the KDE equivalent) can handle colour palettes, which makes it more useful to graphics designers at the moment. However, Agave is still a young project and offers some novel features which anyone working with colour will appreciate.
Agave is available in Ubuntu Edgy (universe) and Debian Etch.