There was once a popular and free software that allowed you to run a virtual desktop on Windows OS, called : Yomd'3D. But this project was taken over by Otaku Software and renamed as Deskspace, which is currently a commercial software.
- 14 -days trial version: Deskspace.
- A free version of Yomd'3D, is still available here.
Fortunately several (free) alternatives exist:
Software with a 3D interface
Without 3D interface
A browser extension for Firefox
This small extension allows you to switch tabs under Firefox using a 3D cube effect: Tab Effect