Ben Reiniger wrote on Wed, Jul 17, 2013 03:08 AM UTC:Excellent ★★★★★
This is especially useful for finding variants in the intersection of various categories. For instance, to find 3D variants where there is some kind of hexagonal component (hex prism or tetrahedral e.g.), set up the search just for 3D variants, then modify the resulting URL so that it includes "category=3D,hexagonal".