Mouse offer only relative positioning: Moving the mouse in a certain direction will move the cursor in the corresponding direction, if you move your mouse to the right but it was facing left, the cursor would just move to the bottom of the screen. There's no relation between the position of the mouse on your mouse pad/desk and the position of the cursor on the screen. But what if a mouse can recognize the motion of it rotating around itself so it always know which direction it's facing to? The cursor would always move to the direction you move your mouse on the desk, if it's known exactly the direction your mouse is facing to. Lifting the mouse up is rather a problem though, but there would be some solutions for it. Sorry for bad English, thanks for reading.