Isotope244
Play Mac games and games for Pocket PC and Windows XP and Vista.
http://www.isotope244.com/

Blueberry 3D-desktop
This project combines OpenGL, Win32 API and Delphi programming and is intended for learners. The desktop is a 3D interface replacing the flat Windows desktop.
http://blueberry.sourceforge.net/

The Mass Interactive Desktop
A desktop environment that looks like an IRIX desktop.
http://5dwm.org/

Blueberry 3D-Desktop
The Blueberry desktop project is made using Delphi, its main purpose is a 3D OPENGL engine in replacement of Windows desktop
http://blueberry.sourceforge.net/

Desktop Manager
Desktop Manager is a virtual desktop program and Windows shell. A virtual desktop program gives you more work space, you use a control of some kind and you switch to another virtual screen where you can run different applications. So, instead of hunting for windows behind other windows on one cramped screen you can keep them separate and switch to them when you need to work with them. A Windows shell is what you see on the desktop, the interface for interacting with the system, it includes the icons, folders, the taskbar, etc. Desktop Manager is what you make of it.
http://www3.nf.sympatico.ca/byronm/dm.html

Desktop-Enhancing Utilities
Desktop-Enhancing Utilities - XDESK (virtual desktop manager) + SysTrayX (tray manager) + XFilesDialog (file-dialog helper)!
http://www.desktop-utilities.com/

Virtual Desktop 1.1
Virtual Desktop Manager - Download award-winning easy-to-use virtual desktop manager with skin and hotkey support; each desktop has it's own running applications, windows,wallpaper; plus many other features.
http://www.easyfp.com/virtualdesk.htm

Greatis Software DesktopKeeper
Utility to arrange the desktop icons in the way that best for themselves. Software includes a virtual desktop manager, wallpaper manager, windows manager, desktop icons protector, desktop intruders' locker and others. [Windows 95/98/ME/NT4/2000]
http://www.greatis.com/desktopkeeper.htm

Meliora: Desktop Xtra
Desktop Xtra allows to control all desktop elements with Macromedia Director or Authrware. Set wallpaper, screensaver, system desktop icons, system colors, system cursors, create custom shortcuts, change visual settings, add items to active desktop.
http://www.meliorasoft.com/xtras/desktop/

Emerge Desktop
Emerge Desktop is an alternate desktop shell (user interface) for Microsoft Windows 2000 and above. It provides menus similar to the standard 'Start Menu' available via a right or mid click on the desktop. In addition, there are many additional applets that provide additional functionality, including a task list, system tray (the icons located on the right hand side of the Windows Taskbar). There are many informational applets that display CPU, Memory and Disk usage. It will even display the weather for you.
http://www.emergedesktop.org