I was waiting at a bus stop in San Francisco near Moscone Center, when a semi-normal looking guy walks up and starts writing furiously on an outside partition of the bus stop structure. I was standing on the inside looking at the bus route map, and he was on the outside, writing away, talking to himself in a funny lisp.
Not wanting to appear too nosy I waited until the bus pulled up before I took a peek at his handiwork. There wasn't much to see since he was using a pencil and the surface he was writing on was gray metal. I hoped he hadn't written down something important like a solution Fermat's Last Theorem or something, because you couldn't read it.
I got on the bus (paying my $1.50) and sat down about half-way back. He then gets on, telling the driver "I need a ride" and does not pay. The driver said nothing, and as the guy walked by me towards the back of the bus he mumbles "market the knowledge-base".
As we pulled away he went to the back, sat up on the back of seat, and at the next stop the driver got out of his chair and told him to sit down properly. I pondered this sequence of events while watching an elderly gentlemen "comb" his sideburns with a toothbrush.