Multi-user per screen actually has some really great use cases, both involving single users with multiple pointing devices, and multiple users collaborating, even on traditional workstation displays. On a white board it is a whole other kettle of fish again.
Multi-pointer X is very interesting in this respect. The problem is, nearly all existing software is based on an assumption of one focus widget at a time, let alone multiple pointers/users interacting with the same widget. Therefore it is not trivial but moderately easy to support multiple pointers each interacting with a different client (already useful), but multiple pointers interacting with the same application to (say) edit different parts of a drawing at the same time (an experience trivially easy with pen and paper, not yet replicated on computer) is considerably more difficult.
I would love for this technology to become more mainstream.
Biting the hand that feeds IT
