CORE (https://core.ac.uk/) aims to aggregate all open access research outputs from repositories and journals worldwide and make these available to the public through a set of services including search, API and analytical tools. As of April 2017, CORE offers seamless access to 70,251,799 open access articles. CORE harvests, maintains, enriches and makes available metadata and full-text content (typically a PDF).
Developed by the Knowledge Management Institute at the Open University, CORE came top in a recent list of top 21 freely available online journal and research databases for academics; https://www.scribendi.com/advice/free_online_journal_and_research_databases.en.html
Jane Daniels commented
I don't have any votes left but would definitely support this!