Huge "collection of all catholic available texts, declared of public knowledge, written in the main Christianity’s languages." Includes writing of the Church fathers (including Migne's Patrologia Graeca and Patrologia Latina), Du Cange's Glossarium Mediae et Infimae Latinitatis, the Monumenta Germaniae Historica, and much more.

Most of the site is in Latin, although there is an About Us page in English. The documents themselves are mostly scanned and converted into PDF format, in their original languages.