"This table helps you to draw precise freehand circles and lines. It is under development by a group in the Yasuaki Kakehi Lab at Keio University.By using a computer to control the XY position of a magnet under the surface of the table, it implements, on paper, drawing methods utilized in computer graphics." http://www.diginfo.tv/v/12-0215-r-en.php#
Found here http://prostheticknowledge.tumblr.com/