I have acquired a decent "field recordings" rig, but haven't used it yet, so I follow the technical aspects of this discussion with interest. In my head, I want to go even smaller, as I don't have the smuggling skills that others have, and I've seen some downright tiny all-in-one boxes, that would pass anything short of a TSA inspection. (And actually would pass that, too, since it's not a weapon, but would be detected.)