I'm looking for a small messenger bag for commuting. I have a large Timbuk2 which I use for grocery shopping. What I want is something that is smaller and more structured (compartments, etc.) I want it just to carry documents plus my U-lock and cable, and occasional articles of clothing, etc. It would be nice if it looks good so that I can be presentable at work.

I am of the persuasion that wears the bag low on the back and carabiners it to my belt so that it won't migrate. Therefore, I need an available clip for the carabiner. I also don't want to spend Chrome/Timbuk2-type bucks. I have seen some bags on Amazon that interest me, but I don't dare buy them without some advice (the ones I am interested in at present are the Osprey float and the Everest W-1003 Crinkle. The Everest is cheap and looks nice but has zero reviews.)