1. A system for providing a positional input value to an electronic device, the system comprising: a sender portion adapted to be manipulated by a user to specify a target point within a target area, the sender portion including a light projecting system adapted to project a pattern of light including a predefined spatially varying characteristic at the target area; and a receiver portion including at least one sensor unit, the sensor unit is adapted to measure at least one value of the spatially varying characteristic of the pattern of light at the location of the sensor unit, wherein the receiver portion includes logic adapted to determine a positional input value associated with the target point from the value of the spatially varying characteristic at the location of the sensor unit, wherein the predefined spatially varying characteristic of the pattern of light is an intensity pattern, and wherein the sensor unit is part of a plurality of sensor units, each sensor unit at a different location and adapted to measure the value of the spatially varying characteristic of the pattern of light at its respective location, wherein the value of the spatially varying characteristic is an intensity of light received from the sender portion, and wherein the receiver portion includes logic adapted to determine the positional input value associated with the target point from intensity of the pattern of light measured by the plurality of sensor unit locations.