Open-access (OA) literature is digital, online, free of charge, and free of most copyright and licensing restrictions.

Definitions

A Very Brief Introduction to Open Access by Peter Suber
 
Open Access Overview by Peter Suber
 
Open Access 101, from SPARC
(a fun 3 minute video)

News

SPARC Open Access Newsletter
Writings and updates.
Open Access Now
Relevant, current, curated news and information about open access and scholarly publishing.

Advocacy

SPARC
SPARC®, the Scholarly Publishing and Academic Resources Coalition, is an international alliance of academic and research libraries working to correct imbalances in the scholarly publishing system.
Creative Commons
Provides a flexible range of protections and freedoms for authors, artists, and educators.
Public Library of Science
PLoS is a nonprofit organization of scientists and physicians committed to making the world's scientific and medical literature a freely available public resource.
Right to Research
Student advocacy group promoting the concept of open access.
Alliance for Taxpayer @ccess
The Alliance for Taxpayer Access is a coalition of patient groups, physicians, researchers, educational institutions, publishers, and health promotion organizations that support barrier-free access to taxpayer-funded research.

Digital Repositories & Directories

SSU ScholarWorks
SSU ScholarWorks collects, preserves, and distributes in a digital format the creative and administrative records of faculty, students, and staff.
CSU ScholarWorks
A page providing access to digital repositories from various CSU campuses. Repositories are important tools for preserving an organization's legacy; they facilitate digital preservation and scholarly communication.
eScholarship (University of California)
eScholarship provides a suite of open access, scholarly publishing services and research tools for scholars and researchers associated with the University of California.
Highwire (Stanford University)
HighWire Press partners with independent scholarly publishers, societies, associations, and university presses to facilitate the digital dissemination of 1308 journals, reference works, books, and proceedings.
DASH (Harvard University)
A central, open access repository for the scholarly output of faculty and the broader research community at Harvard.
OpenDOAR
Authoritative directory of academic open access repositories.

OA Initiatives

Stanford University
School of Education faculty members in June 2008 unanimously voted to allow the university to place their published articles in a free online database.
MIT
Faculty in March 2009 provided open access to their scholarly articles.
Harvard
A total of eight schools at Harvard have enacted policies promoting open access to their scholarly writings.
U.S. Office of Science & Technology
A forum has been launched for public consultation on access to publicly funded research results, such as those that appear in academic and scholarly journal articles.
U.S. National Institutes of Health
A new policy ensures that the public has access to the published results of NIH funded research.