I thought I has blogged this before, but I haven’t, so here it is: Stella is Rob Webb’s astoundingly comprehensive polyhedron exploration application. Starting with an exhaustive list of polyhedra (including some I’d never heard of), he provides a mind-boggling array of operations to perform: dual, stellate, facet, augment. All aspects of the operations can be adjusted, then nets printed out to make models. If you have the time and the inclination, Stella provides an endless set of rabbit holes to explore.