Pick-and-Drop
I came across a link to this cool use of pen based input that may have some interesting applications in the multi-model space. Pick-and-Drop is a concept where you are able to more or less do Drag-And-Drop between computers with a pen and it would behind the scenes being transfered between the computers. Still very much in a research state right now but it could be very interesting to see if anyone can bring something like this to market. There is also an article from the BBC on this technology.