RAMBI: Index of Articles on Jewish Studies: Indexes selective articles in various fields of Jewish Studies and the study of the Land of Israel from thousands of periodicals in many languages. Some full-text. (Sign up for Notification of articles added to RAMBI here)
ATLA Religion Database + ATLAS (1949): Articles, essays, and book reviews covering Biblical Studies, world religions, and religious perspectives on social issues (American Theological Library Association).
JSTOR: Long runs of back-files of scholarly journals in a wide range of disciplines.
ProQuest: A multidisciplinary collection of databases, including Philosopher Index, MLA International Bibliography, and PAIS.