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.

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.