Ingenta is one of the most comprehensive collections of academic and professional publications available online. An excellent (and regularly updated) research tool for summaries, full-text articles and book chapters.
As an infomediary company, Ingenta is devoted to providing access services to academic sources and special tools for librarians and teachers -- including more than 22,700,000 documents overall
As an integrated database, Ingenta provides access to full-text articles in pdf format and to bibliographical data coming from The International Bibliography of the Social Sciences (a BIDS service)
This site is one of the most comprehensive collections of academic and professional publications available online. A special service (HERON), limited to UK academic institutions, provides access to electronic book chapters
While not a PS-specific website, Ingenta covers many of the most important worldwide journals in the discipline
As an access service, the entire database has a perfect updating rate