Microsoft MultiMouse
Our computers already have few USB slots vacant but come January 2007, we will be able to simultaneously work with two or more pointing devices (read mouse) attached to the same computer.

While this new software called Microsoft MultiPoint is being developed primarily for school children in developing countries who have to share a computer, MultiPoint may even be very helpful in improving the productivity of the "privileged crowd" as well. Some possible scenarios:

Case A: You colleague walks in to explain something on your computer screen. With Multimouse installed, you can just pass him the second mouse without affecting your existing setup.

Case B: MultiPoint will be a blessing for the ambidextrous souls who can operate the computer mouse efficiently with both hands. Place a mouse at both side of the keyboard and switch among them seamlessly.

Case C: Pure Fun - Microsoft MultiPoint will let you customize the style of various cursors on the same screen.

Case D: Attach the second mouse as an instant backup like an Uninterrupted Power Supply. When you primary mouse fails or the battery level is low, the alternate mouse will come in handy without interrupting your work.

Source: Microsoft Research India, Press Release