An electronic game in which each player controls his own moving image on a visual display to change the direction of movement of the image as it advanced on the display. As each player's image moves, changing direction on command, it forms a visual "barrier" trail on the display of the path traversed....http://www.google.co.uk/patents/US4089524?utm_source=gb-gplus-sharePatent US4089524 - Digitally controlled electronic game
