This sounds counter-intuitive, but the best (from the technical angle) companies I worked at -- or know friends at -- are muddle the "internal enterprise tools"

This sounds counter-intuitive, but the best (from the technical angle) companies I worked at -- or know friends at -- are muddle the "internal enterprise tools" and "public facing applications" divide quite a bit, but (and here's a catch) when their perceived and actual primary area of competence is building applications that at least somewhat resemble the internal tools in question. Sparkfun is in an odd place, they could call themselves a store, but then again so could Amazon -- it's not clear that selling technology is requisite to technology being a primary area of competence.