BIREME *Portal of Journals on Health Sciences, mix of open access and subscription Journals (primarily in Portuguese or Spanish)
DOAJ *Directory of Open Access Journals (multisciplinary)
Freemedicaljournals.com *promotes free access to medical journals, listed alphabetically, by specialty, or language.
Highwire Press *claims to be the largest archive of free full-text science on Earth! As of May 2007, this archive contained 1,714,694 free full-text articles. 37 journals were completely free sites, while 16 journal sites were reporting free trial periods, and 238 sites had free back issues.
Open Science Directory *free searchable database of the growing collection of articles free in developing countries. This site is provided by EBSCO Information Services.
PubMed Central (PMC) *a free digital archive of biomedical and life sciences journal literature at the U.S. National Institutes of Health (NIH), developed and managed by NIH's National Center for Biotechnology Information (NCBI) in the National Library of Medicine (NLM). The ever growing archive may be searched or browsed by title. UK Pubmed Central (UKPMC) *based on PMC, UKPMC provides a stable, permanent, and free-to-access online digital archive of full-text, peer-reviewed UK publications.