IMAGINE," THE SCENARIO would begin, "a room/place/device/system that will serve all your communication needs for information, entertainment, messaging, home shopping, protective security, banking and much more .... " In countless books, articles, speeches, television documentaries and news programs these and other promises have been made for decades. In his visionary science fiction work, Voices from the Sky, Arthur C. Clarke imagined this and more. So did technologists who thought cable television would be the instrument for multifaceted new media services. Others spoke of a cosy menage a trois of telephone, television and computer, an integrated world of multimedia wonder wherein all forms and functions of communication would converge into a single system, one that some said would eventually be accessible to all people everywhere.