You can imagine that I see all kinds of unsafe riding on campus, but there are three behaviors, sidewalk, wrong way, and wrong side riding, that really get me going. Throw in the ubiquitous iPod earbuds, and we’ve got trouble. I’ve yelled at a few, and they’ve either couldn’t hear me, or look at me like I’m insane. Granted, there are non-automobile areas where sidewalk riding is allowed, but bikes lanes are marked.
(I see bikes on the sidewalk almost daily, but I can’t find a picture of one. I’ll have to go out on a “shooting spree”)