VirtualBox

I'm once again soliciting thoughts on virtualization from ed tech readers (or anyone else who wants to weigh in for that matter). I found a nice walkthrough yesterday on running VBoxHeadless on an Ubuntu server to deliver virtual machines via RDP. VBoxHeadless is a version of VirtualBox designed, not surprisingly, to run on a headless server and manage virtual machines in such a setting. The walkthrough outlined how to create a virtual Ubuntu server within the existing Ubuntu server and make it available on the desktop.

Creating multiple virtual servers of this sort would provide students with a virtual sandbox for everything from web design to database development, create new testing environments for administrators quickly and easily, and, of course, easily manage multiple virtual servers in production environments.

What I'm curious about, though, is the use of VirtualBox in this way for desktop virtualization. Is VirtualBox robust enough to deliver student and staff desktops to thin clients? I'm a year away from refreshing a whole thin client/server backend infrastructure and, as always, am more than happy to look at anything "not Windows". While our Windows Server 2003 Terminal Services setup has actually served us quite well, I'd always prefer to spend more on hardware and less on software licensing.

Tell us about your experiences with VirtualBox. How well does it scale? What have you found works well in terms of server hardware per number of users?