Microsoft has applied for a patent to turn your phone into a graphics tablet for your desktop computer.
The application, dated the 25/2/2010, seems more suited to a device with a resistive screen, states:
A system and method for using a mobile device having a touch screen as a graphics tablet input device for a user computer is disclosed. A graphics tablet application executing at the mobile device displays a simulated graphics tablet surface and, optionally, programmable or nonprogrammable soft buttons. The graphics tablet application configures the mobile device to be recognized as a graphics tablet input device when connected to the user computer and sends an indication of user input to the user computer. A mobile device support pad stabilizes the mobile device while it is used as a graphics tablet input device. A recess in the support pad having length, width, and depth dimensions that are substantially similar to dimensions of the mobile device restricts movement of the mobile device and places the touch screen of the mobile device in substantially the same plane as a top surface of the support pad.
While I know there is plenty of prior art for this concept, hopefully this patent is some indication of some intent by Microsoft to make our phones that little bit more useful while they are charging on the side of your desk
Read the full patent here.