Believer's Web: Collection of articles with searchable index.
Biblical Worldview: Directory of authors, speakers, books and ministries that in the opinion of the site's authors teach a Biblical and Christian worldview.
Computer-Assisted Theology: Internet Resources: Annotated directory. Strong on Biblical studies, historical theology, individual theologians, and publishers. Highlights best resources and new additions. Could take a minute and a half to load.
DataRat Theological Glossary: Extensive theological dictionary from a Reformation perspective.
Fides Quaerens Internetum: One of the earliest guides to Christian theology on the Net. Small. Leans toward institutions (schools, libraries, societies). Kept up to date, but almost no description of links.
Orthodox Theology: Liturgy is theology, iconography is theology, and above all, to truly pray is to be a theologian. But SS. Peter & Paul Church endeavors to introduce the reader to Orthodox theology. Both historical sources and current practice.
Phil Johnson's Bookmarks: Christian and theological links, with ratings and commentary from a Calvinistic Baptist perspective.
The Irish Theological Association: An annotated list of theological resources, split into about 20 categories.
The Online Theological Research Library: One (very) long page with links categorised by subject area.
The Threshold: A navigation tool for finding theological resources on the web. Calvinist.
THEOLDI: Theological and Interdisciplinary Literature: Search engine for texts, monographs, and journal articles. Provided by the School of Theology at University of Innsbruck.
Theology Links: Links to theologians, online texts, journals, essays and papers, and organisations. No annotations.
University of Pennsylvania Library: Christianity: One large page of the most important links.