Multidisciplinary index of over 17,000 peer-reviewed open access journals, covering subjects in humanities, social sciences, STEM, and medicine. (FREE)
Part of SSRN, the Computer Science Research Network (CompSciRN) includes research in information technology and related fields. SSRN's eLibrary provides access to research from multiple specialized networks. Most papers are available to download.
Nonpartisan group that conducts "public opinion polling, demographic research, content analysis, and other data-driven social science research" to inform the public about issues, attitudes, and trends.