But back to the waving thing...

I often wave because I *do* think the person honking might actually know me or think they know me, so I do try and look up and see if I know them. And then there are the nervous "ooh, watch out I'm behind you" honks. You can sort of differentiate them from the angry honking for the most part, mostly because the angry or frustrated people lean on the horn a lot more.

It took me a while to stop feeling a sharp spike of anger whenever people honked, but now that I'm more used to riding in traffic I have a better sense of when people are attempting to be helpful or friendly and when they are being aggressive or obnoxious. I find that it's a lot better for my psyche when I ride with the assumption that most people are just trying to do the right thing, and I think it actually helps me to stay calm even when some motorists choose to behave badly. (I noticed this today with a particularly badly behaved driver.)

that said, I remember waving at a honking driver this past winter and getting the finger in return. Ah well. I *was* being half-sarcastic at the time, so maybe he picked that up.