There an article in the Washington post, I really like the line
I sometimes think that etiquette for urban bikers needs more emphasis. I am always surprised when another cyclist passes me without saying, “On your left.” With parked cars on my right and traffic on my left, those three words can be crucial; I wouldn’t want to swerve left to avoid a pothole, only to collide with a passing biker.
This is critical for biking, we are on narrow paths and dealing with cars and trucks, the last thing we need is our own being inconsiderate and not giving a simple warning before passing.
Just this morning I watched one of the metro circulator buses swerve in and out of M street, first it swerved right as if to stop to pick up passengers then it changed it’s mind and pulled out left hard into the lane in front of me, then it decided to force it’s way into the left lane forcing a black SUV out of its lane before it stopped at a traffic light. What do you know the driver had a nextel cell phone in his hand which he claimed is allowed because it is a work cell phone.