I have been playing around with XNA using DWM, GDI and the good old Win32 API's and think I can create a kind of 3D desktop with them.
The intention is to also leverage the Windows 7 Multi Touch API as well so you will be able to gesture from one application to the next, extract and inject data from one application to the next, all off my XNA desktop.
I still have a number of glitches to iron out, and this clip shows the application just taking the current app that is in use and displaying a 2D representation of it in XNA. As you can imagine, now I have an image of a n application, I can now do anything I like with it in XNA.......Cool eh..
As ever C&C welcome :)