For those with a curious mind generally and an interest in book history in particular (and religion as well!) the launch of the Polonsky Foundation Digitization Project is a must stop spot during web crawling:

The Bodleian Libraries of the University of Oxford and the Biblioteca Apostolica Vaticana (Vatican Library) have joined efforts in a landmark digitization project with the aim of opening up their repositories of ancient texts. Over the course of the next four years, 1.5 million pages from their remarkable collections will be made freely available online to researchers and to the general public.

Just look at the work of those illustrators.