DSpace is open source software used by more than 2,000 academic, non-profit, and commercial organizations for building open digital repositories.  It is free, easy to install "out of the box", and can be customized to fit the needs of any organization to preserve and enable easy and open access to all types of digital content.

Fedora is a robust, modular, open source repository system for the management and dissemination of digital content. It is especially suited for digital libraries and archives, both for access and preservation. It is also used worldwide by academic and cultural heritage organizations, universities, research institutions, university libraries, national libraries, and government agencies to provide specialized access to very large and complex digital collections of historic and cultural materials as well as scientific data

VIVO is open source software and an ontology for representing scholarship used by federal agencies, academic institutions, professional societies, for-profit publishers, and data providers.  VIVO supports recording, editing, searching, browsing, and visualizing scholarly activity. VIVO encourages showcasing the scholarly record, research discovery, expert finding, network analysis, and assessment of research impact