It seems Apple will launch soon a 3d Desktop ... After Linux compiz, Kde 4.2 and Microsoft Vista , Apple is coming with their new 3d Desktop. 
Apple 3D desktop was revealed in their patent filing. But if you are curious just read more here: http://www.macrumors.com/2008/12/11/apple-exploring-3d-desktop-and-application-interfaces/
Google desktop was launched some time ago for Windows and now (after 3 years) they came with a Linux version. For those who doesn't know what it is :
You have lots of information on your computer, and you see a lot more on the web. With Google Desktop, whenever you look at a web page, read an email or edit a file, Desktop indexes that item and copies its contents into your local cache, so you can quickly and easily find all this stuff right when you need it.
