Science
Some Free Online Resources
National Center for Biotechnology Information
PubMed Bibliographic database of biomedical and veterinary literature; 24+ million citations, some free full-text
Science.gov: Database of U.S. government scientific publications; free full-text
BioMed Central (BMC) Directory of open access journals and selected free full-text articles published by BMC in the fields of biomedical research, medicine, and veterinary medicine; for articles not in collection, use search box or subject tabs and follow links to journal websites
PubAg: Portal to USDA-authored and other highly relevant agricultural research; 40,000+ free full-text articles, bibliographic entries for 340,000+ articles; no subscription required
Base Digital Library for all subjects including sciences
WorldWide Science - Global science gateway to national and international scientific databases and portals.
SciElo - Open access to international science papers and research.
Analytical Digital Sciences Library: Student Science - Award-winning magazine and database of current topics, trends, and research in the scientific fields.
The ArXiv: a free online database with publications relating to physics computer sciences, mathematics, finance an biology.
Elsevier Open Access Archive : Includes many subjects like math, biology, chemistry , medicine and more
Economics
Econ-Biz: Journal, papers, conferences and others
National Bureau of Economic Resesarch
Econ Stor - Some papers and case studies are available in the open access category.
Journal of Central and Eastern European Economic and Management
RePEc - Research Papers in Economics is a free and open source database of economics papers and research.
Multi-Disciplinary - All subject Access
Some Open Access Databases - (Multidisciplinary subjects)
Elsevier Open Access Archive : Includes many subjects like math, biology, chemistry , medicine and more
Book and journal content from the collections of a partnership of major research institutions and libraries, digitized and made public; free full-text
Collection of articles from 2450+ peer-reviewed open access journals; multidisciplinary; free full-text
Bibliographic database of scholarly books and articles in the Library of Congress, National Library of Medicine, arXiv, IngentaConnect, and Research Papers in Economics (RePEC); multidisciplinary; 40+ million citations; alerts and other tools
Portal to 3000+ scholarly journals and other publications partnered with HighWire Press (Stanford University); click "For Researchers" tab to search for articles; some free full-text
Search for articles in 13,500+ scholarly and professional publications on a range of topics; some free full-text
Jurn: Search tool for open access content
DOAJ: Directory of Open Access Journals 16,710 Journal 6,402,372 articles
Core: Open access research papers over the last 10 years.
Cogprints: A variety of subjects includes open access of papers
National Digital LIbrary of India
Base Search -Bielefeld University Library
Directory of Open Access Journals - A community-curated online directory that indexes and provides access to open access, peer-reviewed journals.
Indiana University and Purdue Research Database
POPLINE - An online databases with links to articles (often free) relating to health and associted factors such as culture and society
Visual Arts and Film
Google Arts & Culture: Museum explorer, 3 D interactive art and tours. Includes cultural interactive experiences.
FILM
TV Tropes - A resource to look at what the Film and TV Tropes are for stereotypical roles in cinema and TV
BBC - Genre Episodes
Documentary Storm - Provides free documentaries in a number of categories
New York Film Club: Provides short documentary films, most under 10 minutes, and related discussion questions.
Primary Sources
History
Historical Text Archive of USA
US National Archives A huge databases of primary and secondary sources mainly on US History.
Michigan State Uni Library includes some sources in the public domain
Digital History: Includes American history, World Wars and other topics related to • Advertisements • Architecture • Art• Beauty & Fashion
• Cemeteries • Children • Controversies • Courtship • Decision Making • Film • Historiography • Immigration & Ethnicity • Music • Photography • Political Cartoons • Private Life • Propaganda Posters and more.
Health
MedlinePlus - U.S. National Library of Medicine.
PubMed Central (PMC) - Is a free full-text archive of biomedical and life sciences journal literature at the U.S. National Institutes of Health's National Library of Medicine.
PubPsych - Psychology database of open access journals.
CogPrints - An electronic archive for Psychology, Neuroscience, Linguistics, Computer Science, Philosophy, Biology, Medicine, and Anthropology.