1. User interaction system, comprising: an electrical apparatus ( 110 ); a portable pointing device ( 101 , 300 ) operable by a user for pointing to a region in space; a camera ( 102 ) taking a picture; and a digital signal processor ( 120 ), capable of receiving and processing the picture, and capable of transmitting user interface information (I) derived from the picture to the electrical apparatus ( 1 10 ), wherein the camera ( 102 ) is connected to the pointing device ( 101 , 300 ) so that in operation it images the region pointed to characterized in that the user interaction system further comprises a pattern creation means ( 116 ) to exhibit a characteristic pattern that is created for identification purpose by the pointing device of the pattern creation means associated apparatus.