Bibliotheca Philadelphiensis houses its digital collection at the Internet Archive and represents holdings of libraries in the Philadelphia area, including “Princeton, Bryn Mawr, Villanova, Swarthmore, and many more college and university libraries, as well as the American Philosophical Society, National Archives at Philadelphia, and other august institutions of higher learning and conservation.” More information can be found at the Open Culture website.
La Bibliothèque virtuelle des manuscrits médiévaux (BVMM) is a digital library of medieval manuscripts from French libraries across the country (but not the National Library) made available by the IRHT (Institut de Recherche et d’Histoire des Textes). The interface is in French but easy to use. There is a map view that allows you to browse by city.
Manuscripts Online enables you to search a diverse body of online primary resources relating to written and early printed culture in Britain during the period 1000 to 1500. The resources include literary manuscripts, historical documents and early printed books which are located on websites owned by libraries, archives, universities and publishers.
As described at the project’s web site, Manuscripts Online has not “created any new digital content. Instead, it provides integrated access to electronic content already available on distributed websites. Our search engine does not search these resources directly. Instead, it searches indexes we have created from the full content of each resource.”
Note that some of the resources searched can only be fully accessed with a subscription. The tool will allow users to search these resources and examine snippet results free of charge but does not provide full access.