Originally Posted by
hubcap
If you find yourself frequently going back and forth between wishing you had a pannier(s) and then wishing you had a backpack during your commute, an Arkel Bug might be the solution.
http://www.arkel-od.com/us/all-categ...ing-bag-1.html
I have owned a couple of them and really like them. Though for the last year or so, I have just been using Ortlieb bike packer plus panniers on my normal work commute since I don't mind carrying them with the provided shoulder strap and I like the 100% waterproof reassurance without needing to rely on a cover.
That might be perfect but it's a bit pricey. I've never seen those at my usual bike shops so I can't tell if it would work with my rack.