Gizmodo reports: [edited]
Before Ma Bell came to town, it was barbed wire that brought rural communities together. A Sears telephone hooked up to barbed wire — miles of which were already conveniently strung along fences — connected far-flung ranches in the recently settled American west. Thus an ingenious and unregulated telephone system sprung up a hundred years ago.
Since the system had no switchboard, every telephone along the fences would ring at the same time. Each house had its own distinctive ring — two short one long, for example. Of course, when things got lonely out there on the ranch, there was no guarantee of privacy.
Talk was free, and so people soon began to 'hang out' on the phone, just as they do today in online social networks. People would read the newspaper over the telephone, they'd have musical nights where someone would play their banjo, someone else would sing along, and others would listen.
The shared line could even serve as a rudimentary broadcasting system. On many fence-phone networks, a single, very long ring would signal a 'line call', an announcement of interest to everyone on the system. This might be a weather report, weekly livestock prices, word that the train would arrive late, or news of an emergency such as a prairie fire.