www.mesh.com is interesting new member of the Live Services family that is enabling users to have "on-line" Desktop that has folders/files that are synchronized with all your computers and now mobile devices too: http://blogs.msdn.com/lokeuei/archive/2008/11/04/live-mesh-tech-preview-for-mobile-available-now.aspx
Beside folder/files synchronization, it also enables you to add device to the collection of the devices that can be accessed with Remote Desktop as well as other new features that are coming soon!