So, here's a little relevant information:
"lane splitting" in california is legal. Lane splitting is riding in between lanes of traffic. Motorcyclists typically do this on the freeway when there's traffic and no one is moving, so they ride between the lines of parked cars. Anyway, it's also legal on city streets, and for bicycles.
So, this morning:
I was riding a route that I don't normally take to work. I had just made a left turn onto a 5-lane, one-way street, so I was at the far left side of the street. I needed to be at the right side of the street to make a right turn. Traffic wasn't moving, everyone was waiting at a stoplight almost a full block ahead.
I started riding, doing my lane splitting thing, and whenever there was a enough room in front of a stopped car, I'd move over one lane to the right and continue. Well, I was moving to the right, about two lanes over from where I started, and I began to pull into the space between lanes. At that instant, a young guy on a moped sorta thing (looked kinda like this), went by me in that same space. He looked back and sort of glared at me through his full-face helmet, and I shouted "Sorry" and gave him a "sorry' wave, and he kept going.
I do this lane splitting thing all the time, but I guess I've gotten used to the fact that hardly anyone else does it in the city. Most of the streets are too narrow for motorcycles to fit between cars, and most bicyclists stick to the edges of the road.
From now on I'll have to be more careful to check the space between cars before I start using it as my own lane.