Just curious, when you say that you think it's feasable, are you basing that on some particular technical knowledge, or is it more in the relm of wishful thinking?
From what I understand, you would have to find a DFP20 interface that would drive this particular screen. I did see an evaluation kit a while back which included a PCI video card with DFP-20 connector, and the DFP-20 interface board that connects to the flat pannel, but the list of supported pannels was pretty small, and the eval kit itself was around $1,000. I think that the cost of adding support for a new pannel was also around $1,000, which would be negligible if 1,000 of us or so chipped in.
My guess is that adding a "video in" is on par with using a CRT monitor as a video camera, or using a scanner to print. You are right though, it would be cool if it were possible.