There are a few ways to tell you've found a University of Chicago student while in the Loop: frantic avoidance of eye contact, faces covered in ink from falling asleep on notepads, full knight regalia, pirate hats. But the easiest way to determine that you have absolutely, positively come across a U of C-er is to wait and see what happens when he or she runs after a bus.Very few people look good running, and fewer still while running desperately after a #6 bus and waving at an indifferent bus driver. But it is the backpack run that gives him (or her) away as a creature of Hyde Park: a weighted-down, side-to-side, bobbing, frantic jostle that only years of running to and from the Reg in below-freezing conditions can produce.The point is that U of C students as a whole spend a whole lot of time in libraries. A great deal of that time is spent with pens and excellent reasons to procrastinate, and that means that the cubicles and whiteboards across the seven floors of the library are covered in graffiti - with a typical U of C twist. The LA Times reports that Quinn Dombrowski, a University staff member and researcher, documented the work of generations of book-crazed studiers (and sure champions of the backpack run) in an extensive Flickr collection, and the result is pretty neat.There are literary references and polls and pictures and questions and general declarations about humanity. It's sort of like bathroom graffiti for the Plato-inclined.