Looking for virtual desktop

[Xaius]

I remember reading in the past about a kind of virtual desktop that opens up a window, which contains a desktop, on top of your normal desktop. Now I'm not referring to the kind of VD like you get in Linux where you click a button at the bottom to switch to a clean desktop. I'm referring to a window popping up, which contains a desktop separate from your normal desktop. In this "virtual" desktop, you can surf the web without having to worry about spyware, because it would only be installed on your virtual desktop and have no access to your normal desktop or system files, and as soon as you close the virtual desktop, any changes would go away. So any malware that got installed on the VD would simply disappear. But I can't find any freeware programs like that. Does anyone know of any I can download? Thanks