I often read predictions about future technologies from analysis companies like Gartner Group. These studies often strike me as awfully linear in their view on development. I would, therefore, like to know examples of people who have been able to predict the consequences of technologies that have radically changed communication. I use a very broad definition of communication, to include transportation infrastructure, so predictions on the impact of things like a postal service, the train, the automobile, telegraph or a modern thing like Twitter are all interesting.