Good friend of mine created Desktop Panorama a virtual desktop environment, after working on it for about thousand hours he recently decided to make it open source.
Hats Off To You, My Friend<p>Panorama has a user friendly design and it is very intuitive.
The mechanics are simple, you can drag and drop windows in and out of the square, which can give you a better overview.The layout of the program is fairly nice. You can switch between a number of skins and the overall design looks very well.
In theory, you have an infinite number of windows you can move around.