If you interested in existing pen-based UI that is pretty awesome check out Ken Hinckley's work. He's a researcher at MSR and has plenty of cool videos on his w

If you interested in existing pen-based UI that is pretty awesome check out Ken Hinckley's work. He's a researcher at MSR and has plenty of cool videos on his website. http://research.microsoft.com/en-us/um/people/kenh/ http://research.microsoft.com/en-us/um/people/kenh/