(telephone sidebar: The advent of the telephone coincided with a serious reduction in mail service, which had previously run as often as 4x a day in large cities, and generally resulted in the further isolation of people from their communities (even as it enabled people to connect to new communities!) I think the telephone is good, and I'm glad that it reached widespread adoption, and I think it would have done so regardless. But I also love to think about what adoption of the telephone, or the cellphone, might have looked like if there was less money to be made in monopolizing the system. It's a useless thought experiment, but it compels me.)