General Theological Resources Online:
Michigan Electronic Library. This list is strongly interfaith, pointing you to resources, books and periodicals, related to many faith traditions.
The Internet Theology Resources Collection of the Alcuin & Clemens Library of St. John's University. St. John's is a Catholic school in Collegeville Minnesota, and its collection is Catholic-based, but very broad in scope. It includes a list of links to online theology-realted periodicals.
Theological Journals on the Net: This listing is from the University of Calgary, and covers journals from a wide range: Jewish, Islamic, Hindu, Buddhist, Christian, and even Skeptics.
A New journal not on the Calgary list is the Journal of Liberal Religion, a Unitarian online publication. The initial issue was very challenging, and it is worth keeping up with.
The Toronto Collection: An extensive listing, mainly Christian-oriented, assembled by the University of Toronto.
Writings of the Early Church Fathers: (Unfortunately, the writings of the early church mothers have not been preserved....) An extensive and easy to use site.
Bible study Tools:
Online Bible StudyTools from Crosswalk.com is an excellent and diversified site, including access to lexicons, concordances, and numerous versions of the biblical text.