TopDesk has added a mode that allows you to flip through open windows in much the same way that Windows Vista's new Windows-Tab key combination offers. It's definitely very cool to look at, and Otaku Software has done a good job of making the application very fast, considering XP is not geared in a native way to provide a 3D view of open windows. The classic TopDesk views are also worth a look, providing Expose-style overviews of all open windows.

TopDesk is a commercial program, and a license costs $9.95 USD, however it has a very generous 30 day trial period.