Jeremy L.wrote a review of Mountain Hardwear Kalispell Backpack - 1750cu in on April 1, 2011
I got this to carry as an everyday pack (to work, on my bike, around town, etc.). For these purposes it is excellent. It's a little hard on the bike, the pack doesn't wrap around you back very much, the padded back sheet is very stiff so it stays flat, and that pulls the shoulder straps out a little. But just use the chest strap and it keeps that from being a problem. This thing is totally bombproof though. I don't see needing another commuter bag for a very long time.