Featured here is an important subscription-based resource for obtaining science articles online. Wide-ranging institutional access as well as free services make each of these resources useful without an individual subscription. The PNAS, claiming to be the "world's most-cited multidisciplinary scientific serial . . . , publishes research reports, commentaries, reviews, perspectives, colloquium...

"The Quaternary Research Center (QRC) fosters interdisciplinary research on the last two million years of the global environment: a time which encompasses massive, abrupt changes of climate, sea level, global biota and ice extent, as well the evolution of humans and the advent of civilization." Divided into six laboratories, the University of Washington's Center studies Cosmogenic Isotopes, Stable...

Based in Washington DC, Resources for the Future (RFF) is an independent, nonprofit organization devoted to the economic aspects of environmental issues. RFF scholars examine topics such as government regulation, risk, biodiversity, climate, Superfund policy, technology, and outer space in a variety of freely available discussion papers, articles, project summaries, and reports [.pdf]. An archive...

Located in North Carolina, the Research Triangle Institute (RTI) is a research institute that is "dedicated to improving the human condition by turning knowledge into practice." Visitors interested in seeing some of the projects RTI is working on will find the "Ongoing Projects" link under the "RTI Newsroom" tab helpful. There is a 3.5 minute slideshow that shows a relevant image, gives a brief...

The Aspen Institute was founded by Walter Paepcke, a Chicago businessman, in 1950 after he was inspired by the natural beauty of Aspen, Colorado. The basic mission of the Institute is "to foster enlightened leadership, the appreciation of timeless ideas and values, and open-minded dialogue on contemporary issues." With locations around the United States and various partner locations in Europe and...

The Heritage Foundation is one of the best known conservative think tanks in the U.S., and its Web site offers voluminous information on various topics. Its publications library offers full text in twelve subject categories from its "FYI," "Heritage Lecture," "Backgrounder," and "Executive Memorandum" series. Selected stories from "Policy Review: The Journal of American Citizenship," are...