Heh, I suddenly realized that I "almost" ran a cyclist down this morning because I thought he was a pedestrian... I didn't actually get anywhere near him, but I was in full flow along the very busy bike path that every morning hosts the local "Tour de Finance", and had to switch sides from left to right, crossing the path of a couple of pedestrians walking towards me with plenty of space to spare. But just as I check my back and swing out to switch sides I see a blur in front of me. I just have time to think "Whoa, THAT'S not a pedestrian!" and swerve back.

Just goes to show, when making split-second decisions it's not always easy to see what's what, and it's especially hard to judge the speed of someone heading toward you - the same way many drivers misjudge the speed of cyclists.