The entrance to the David Rumsey Map Center at Stanford is via a staircase whose walls are illustrated with maps from the Center’s collections. To mark the Center’s 10th anniversary, RJ Andrews and Ray Marshall engineered a pop-up papercraft model of the stairwell. The keepsake opens up to show every wall on every level. Produced in limited quantities and unfortunately not available for sale. See RJ Andrews’s post and Ray Marshall’s web page for how they did it, and images of the keepsake.