Just to say that you might like to know that I've been working on a similar concept. Its called eScape and it allows you to have a 3D interactive wallpaper/desktop. You can rotate the view, and walk around, etc. even load applications by double-clicking 3D objects.
If you fancy a look, its on my site: http://www.liquidream.co.uk
It's very much a work in progress and I haven't done work on it in ages, but one day I hope to find time to get back to it.