..reading the back of someone else's newspaper on the train.
Reading these, I was reminded of when my son came home from college for the summer several years ago. The neighbor's wifi signal from across the street was stronger than ours from downstairs. He did what any enterprising young man would do... he attached to the stronger signal. Several weeks into the summer the neighbor called in shock that the boy had been "using" their wifi. I asked the neighbor where he got his Internet service, knowing full well that there was only one provider at the time. When I suggested that we were all sharing the same pipe anyway, and that sharing the air was not such a big deal, he was actually fine with it. He just had to think it through a bit first.
Personally, I love to watch the neighbors hit my open wifi. They access some weird stuff...