Free Medical Journals Online(http://www.freemedicaljournals.com/) Free journals offering full-text online, ranging from basic science and chemistry to microbiology and toxicology.
HighWire(http://highwire.stanford.edu/lists/freeart.dtl) An archive for back issues of selected scientific journals. Access 618,598 free full-text articles. Note: Not all of their articles are free, full-text.
The Public Library of Science: Biology(http://biology.plosjournals.org/) The pioneering new open-access journal co-published by Harold Varmus, former NIH Director.
PubMed Central(http://www.pubmedcentral.nih.gov/) The barrier-free NIH repository for peer-reviewed primary research reports in the life sciences, which began accepting journal articles in January 2000.