PsycINFO: Contains citations and summaries of journal articles, book chapters, books, and technical reports in the field of psychology and psychological aspects of related disciplines including medicine, psychiatry, nursing, sociology, education, pharmacology, physiology, linguistics, anthropology, business and law.
Sociology: Full text of articles on such subjects as Childhood, Contemporary Sociology, Comparative Sociology, Consumer Culture, Classical Sociology, Ethnic Studies, Gender Studies, Leisure Studies, Social Theory, Sociology of Sport, and Sociology of Work and Employment (Labor Studies).
The Philosopher's index: a bibliographic database with informative, author-written abstracts covering scholarly research in all areas of philosophy.
ScienceDirect: Contains abstracts and articles from the core journals in major scientific disciplines.
CSA Illumina: A multi-disciplinary database that allows you to search biology, communication, philosophy, political science, psychology, sociology and many other disciplines at once.
Google Scholar: Provides a search of scholarly literature across many disciplines and sources, including theses, books, abstracts and articles. Use the "Find it at Stanford" link to get to Full-text (when available).