Computer Aided Analog Design

Drawing on paper has many advantages, and sometimes is simply more pleasing. I propose a ruler with a keypad and a small display on top, and the inner workings of at least three optical mice below. There is also a pin at one end, and a movable hole in a side-slider. In between is a chip integrating the information from the mice and the linear positioning of the side slider. The ruler can be used as a standard ruler, but you can also use it, then hit a button, move it around and get the angle it is now in, relative to the first position. If you lower the pin first, and insert the pen into the hole, a part-circle of defined radius and angle can be drawn. Also, circle through three points, parallels, many geometric figures etc.