We have some resource-restricted K-12 environments looking at this, as well as Microsoft's Windows MultiPoint Server 2010 to save money on workstations and power infrastructure. Fair warning, the Microsoft site seems practically devoid of substantial implementation detail and is more geared toward the kind of fluffy K-12 marketing that makes school administrators spend your tax dollars. I think it's somehow using USB keyboards, mice and monitors — but I haven't been able to tell.
These technologies seem to be under consideration in place of, say, a "nettop" (atom-based) lab running workstation management for ease of administration, and possibly one of the many teacher-snoop-and-control software applications for managing their use. Given state testing requirements, most of our region uses Windows or Macs for compatibility with their testing software. The Macs are generally too expensive for regular purchase cycles, but it's apparently easier to find grants for them as opposed to PCs.