Sustainable Technology Refresh Cycle

If you could apply a BIOS update or load a small control kernel on a regular PC (or MAC if Apple would allow it), and then attach 4 sets of keyboards, mice, and monitors, and load 4 copies of Windows XP, or Linux, or Windows 7, would you? That would allow you to replace one PC every cycle, not 4. I am responsible for rolling out new products at K-12 schools. I just joined Classroom 2.0 and I notice that there is some talk about our product, Fiddlehead. As CTO, my job is to make sure that the product has as many teacher and IT-centric features possible. The product we are rolling out right now is designed to allow schools to adopt a SUSTAINABLE technology refresh cycle. It is not a thin client, but has the cost savings associated with a thin client. It has a Windows desktop (XP, Vista or 7...or Linux), and can run opens source applications at the same time. It doesn't have the weirdness associated with thin clients or server based computing. From the teacher and the IT persons' perspective it looks just like 4 PC's, but on one CPU.

So I guess my question is, what would this product look like if you (as teachers and IT professionals) could design it? ...and if you are interested in telling me what you want to see, would you like a copy of the update and extra video card? I appreciate the input.