I've gotten to the point where I call out "Stopping!" when approaching a stop sign when other riders are behind me. I've been shouted at enough by angry cyclists who had no intention of stopping at signs, so now they get my warning that I'm going to obey the law.

I did my first century on Saturday (Holland, MI), and during the ride, there were a couple of guys who were just about to overtake me as I yelled out approaching a sign. Luckily they followed my lead. One or both of them would have been hit by a car which was shielded from view by a cornfield. The car did not have a stop sign in that direction. One of the guys said he was glad I said something because he wouldn't have stopped. I wonder if he learned his lesson.