It is not uncommon that I have to schlep around a banker box of paper for my job. The combination of thin cardboard, heavy boxes, and two flights of stairs to my workplace mean that sometimes it can actually hurt to carry such a box.
Reminded of langfordw's ergonomic plastic bag handle ( http://www.thingiverse.com/thing:3230 ) I quickly sketched this up in OpenSCAD and cranked out an STL. This is clearly less sophisticated and less ergonomic langfordw's, but I think it will do the job nicely.
Unassociated tags: box handle, cardboard box handle
The author marked this model as their own original creation. Imported from Thingiverse.