I was driving yesterday and stopped at a 4-way stop - a cyclist with no helmet wearing headphones saw me stop and decided to speed up and turn left (in front of me) without stopping or signaling. Grr. And I try to be so overly accommodating to cyclists...usually...but I leaned out the window and yelled at this guy. At least I went with the assumption that he probably wouldn't stop so I hadn't already started out of the intersection. One life saved, for now.