In our article earlier this week looking at the status of X.Org 7.4, one of the features originally planned for integration in this X Server release was MPX, or Multi-Pointer X. While it's been in development for over two years and has been at an experimental state, it's been featured in popular YouTube videos as this is the technology on Linux that allows multiple keyboards and mice to be attached to a single system and MPX allows these input devices to function independently on the same windowing system. For those of you interested in this desktop technology, it's been announced that MPX will finally be merged into the mainline X.Org tree later this month.
It'll be fascinating to see what applications arise to take advantage of this. I have a Wacom tablet with multiple devices - I remember seeing a demo showing someone using the mouse and a pen to manipulate an object simultaneously. I could see Blender getting some interesting controls (particularly in Sculpt mode).
Beyond that, I wonder what desktop paradigms will change if users have easy access to two or more devices. The laptop I'm using right now has mouse joystick and touchpad, so it could immediately make use of two pointers. Stretching windows is an obvious application but I'm sure that there are plenty of other ways of using two pointers more effectively. After all, we all lust after that system from Minority Report!