Totally distributive toposes

My preprint "Totally distributive toposes" (http://arxiv.org/abs/1108.4032) has been updated to include an additional corollary, namely that the totally distributive categories with a small set of generators are exactly the essential subtoposes of presheaf toposes [C^op, Set], which were shown by Kelly-Lawvere to correspond to idempotent ideals in the small category C. Some minor additional changes have been made, and the title has changed. Regards, Rory [For admin and other information see: http://www.mta.ca/~cat-dist/ ]