The conversion to digital technology means that every work of utility or beauty, every computer program, every piece of music, every piece of visual or literary art, every piece of video, every useful piece of information--train schedule, university curriculum, map, chart--every piece of useful or beautiful information can be distributed to everybody at the same cost that it can be distributed to anybody. For the first time in human history, we face an economy in which the most important goods have zero marginal cost.