The (exaggerated) contact geometry used for robust simulation of boxes. We add contact "points" (epsilon radius spheres) to each corner, and have a slightly inset box for the remaining contacts. Here is the interactive version.
Could you explain why (if) the choice to inset the box collision geometry is important? (As opposed to being coincident with the visual geometry)
Also, are different contact filters nontrival? Ie do corner spheres of different objects contact.