If you wear a suit, I am not convinced that any backpack can look professional enough (IMHO, YMMV), and it will ruin your jacket. I know I couldn't use a backpack for professional purposes. That said though, has anyone used the Waterfield Designs Staad backpack? http://www.sfbags.com/products/backp...d-backpack.php

It's obviously only suitable for a very light load, not the full "office on my back" scenario, but in the black-on-black version it looks interesting.

Thoughts?