I perosnally like using the "Virtual Dimension" a free software that allows you to have multiple desktops in MS Windows (similar to KDE and GNOME--sad MS does not include this feature in Windows) It is especially good when I code or design stuff. I know there are many alternatives, and believe me I tried most of them. This one proved to be the most stable and functional.
you can get it from: http://virt-dimension.sourceforge.net/
I usually use it in conjunction with gipo utilites (also free) in order to achieve things like making windows always on top, transparent, etc. You can get it for free from: http://www.gibinsoft.net/gipoutils/index.htm .
Anyone else uses those?