No, not just science fiction. I spent the last few days as the Citrix iForum and it looks like virtual computing is going to be a big thing in the next few years.
What is virtual computing? The idea is that instead of one computer running one operating system and one group of programs, you set up a "computer within a computer" to do your work.
For instance, anyone can download Microsoft's Virtual PC for free. Once installed, you have a second computer on your first one. I use it to install software for testing. Once the test is done, I can discard the changes and have a clean computer. I have one virtual computer set up like a lab computers -- all the configurations are the same. I can test software on it without leaving my desk.
It's even more useful on the server side. If the computer where your virtual server resides is having problems, you can switch applications to a different computer, make the fix, and switch them back -- without any users noticing the difference. Instead of using one server for one application (and have it being used at 10% capacity), you can put several applications on one server and use it at 75% capacity, an efficiency of use that is bound to be attractive.
And then there are the real cutting edge devices. I saw several models of notebook computers without hard drives: they connected with a virtual server via fast wireless card and ran all programs from the server.
We're implementing some of this here at Siena; several of our applications are on virtual servers, and we're using Citrix to supply desktop programs to users in a virtual fashion. But by the time current freshman graduate, there's a good chance that their first job will be using virtual computers for all their work.