Is it possible to have Xen (or other visualization packages) installed in desktops and cluster them together to act as a single server?

For example, let say I've 50 desktops. All 50 desktops run linux and windows in parallel. Windows will be the primary OS, and linux will work quietly in the background. The idea is to use the desktops' extra resources to create a reliable computing environment.

Some advantages I see are as followed:
1) the desktop user won't see a difference because they are still working with windows
2) eliminate the need to have a large server room
3) don't need as much server; thus save money
4) redundancy?

What do you think?

Great idea!
But what about security?
(Physical and the users who mistakenly restart their desktops?)

Better way why don't you start windows on virtual machine based on linux physical node?(Don't expect that softwares to be free)


But if those problems are resolved its a great thing to do, to save resources