Developed by a group of students from Leiden University, this "Force Feedback ShockMouse" is basically a device that serves as a "haptic feedback provider between the computer and the user -- it is aware of the user's mouse gestures and can either do nothing, attract the mouse to a new position, or it push away from its current position." Video demonstration after the jump.
The FFM is a box on which the user can move around a specially equipped mouse. It has an Arduino i i/o board inside, which controls the servo-motors that position an electromagnet along the X and Y axis corresponding the mouse position. It also controls a relays board which sets the polarity of the electromagnet (which can be turned off, push, or attract).