One day last year, while walking in downtown Palo Alto, I saw someone on the sidewalk, walking in circles, gesticulating and yelling. Homeless person, I thought, my urban defense radar ticking up a notch. As I got a bit closer, I could tell my original impression was wrong. He had a Bluetooth headset linked to his cell phone, and was breaking up with his girlfriend.
It was only fitting. I’ve seen a couple homeless people talking to themselves, but holding one hand up to their ear, as if they were having conversations on their cell phone.