EuroDocs: This compendium of European primary sources contains links to transcribed, translated, or facsimile-reproduced sources. EuroDocs was created by Richard Hacken, European Studies Bibliographer at Brigham Young University. The database is searchable by country or time period.
European History Primary Sources: A website with hundreds of links to primary sources based on European history. It contains a listing of numerous digital repositories and is searchable by language, country, and time period. I’ve only delved a little into the EHPS, but it is quite phenomenal. EHPS is managed by the Department of History and Civilization and the Library at the European University Institute.
Connected Histories: Connected Histories is a digital project which brings together 22 major electronic resources on early modern and modern Britain (1500-1900) into an one integrated website with full search functionality. It was created through the collaboration of the University of Hertfordshire, the Institute of Historical Research, the University of London, and the University of Sheffield. Each resource has its own entry page that include links, strengths and weaknesses, resource components, and other information. Overall a great and useful tool for research.