I don’t know who started it, but I love the fact that whenever people on a boat or ship pass you (especially when you yourself are on a separate boat or ship), you wave to each other. You sometimes see this phenomenon with people on those open-top tour buses as well. There you are standing on a city corner, stewing about something and waiting for the light to change, when a bright red, double-decker bus with no roof (or sometimes shaped like a duck) glides by, full of smiling faces and hands waving your way. Only the Scrooges resist waving back.
What’s odd is that this phenomenon simply doesn’t translate to other public arenas, even if it’s the exact same people involved. Sitting on a crowded city bus, my back to the window, facing the people sitting just a few feet away, I imagine that if I started smiling and waving, at least one of them would come over, punch me directly in the face, and ask me (rhetorically) what the hell was wrong with me.
People are strange when you’re a stranger, unless you’re on a boat, or a tour bus shaped like a duck.