This is the bag I wear everywhere. Although it was the second one I ever made (ugly aesthetics) it remains the most useful thing I've ever strapped to my back. The 'utility' bag does everything. It is basically a high volume bag with a very flexible strap/compression system, cordura bottom, bartacked everything, and a dry-top (Arctery'x now has a dry-top backpack. I did this two years before they did). For normal school use, I throw a couple books in and tuck the top fabric in. The straps snug it up so it doesn't rock around while biking, and all is well. In a deluge, roll the top down tight and clip it shut. Have yet to have anything inside get even remotely damp (It's made of waterproof fabric). The back and shoulder straps are covered with bright fabric and reflective tape so I don't get run over biking in traffic, and the liner is bright bright yellow so I can actually see the bottom of the bag peering into it. Inside a velcro patch attaches a modular pocket (that I move between different packs) and a keyclip. The straps system is generally set up as seen in the pictures. However, nothing is sewn in, so it is infinitely adjustable and flexible. I've strapped all kinds of things inside and outside this bag, anywhere from framing lumber to more climbing gear than you can shake a stick at. This bag has biked long days, climbed alpine peaks, come swimming, lead long multipitch climbs, and performed well throughout. The only downside is the ugly brown color, and the complexity for the impatient backpack wearer.
