I am looking for a messenger bag to supplement my backpack for school, specifically for bad weather. I have noticed my notes and books getting damaged by rain when I am walking across campus, so most important is that the bag is waterproof. The bag needs to be big enough to carry standard spiral notebooks and 8.5 x 11 size papers/pads without squishing. I also occasionally take my laptop, which is something like 8x12 (a bit longer than a sheet of paper), but I dont need a separate laptop compartment. My current backpack is ~750 cu (black diamond bbee) which is fine for me. It would be nice if there were a few pockets on the inside for gadgets or some way to hold a water bottle but it is not necessary. I dont want a leather bag or anything that requires special care. Other things I might carry: lunch (in tupperware), clothes (coat or fleece stuff or gloves and hat or change of clothes for gym) The catch is that I want the smallest bag possible. I often carry very little (one or two notebooks, pencils, water, snack, spork, cash) and dont want a big, poofy, empty bag. I have checked out timbuk2 and like the x-small classic messenger but have a bad sense of size from reading dimensions. Do you guys have any advice or suggestions?