arXiv is a free distribution service and an open-access archive for millions of scholarly articles in the fields of physics, mathematics, computer science, quantitative biology, quantitative finance, statistics, electrical engineering and systems science, and economics.
Contains a listing of journals published by Columbia University Libraries. The journals are from a range of academic disciplines all are offered as open access.
The Directory of Open Access Journals (DOAJ) is a unique and extensive index of diverse open access journals from around the world, driven by a growing community, committed to ensuring quality content is freely available online for everyone.
Elsevier offers free access to archived material in 140 Elsevier journals. Articles featured in the archives are free for everyone to read and download. The link above will provide a listing of all journals in the Open Archive along with the embargo period before articles are made available.
PeerJ offers 7 peer-reviewed open access publications covering biomedical science, computer science, organic and inorganic chemistry and other fields in the sciences.