JSTOR Provides full-text content from core scholarly journals in the humanities and social sciences. Coverage is from the earliest issues of a journal to within approximately 5 years of current publication.
Oxford Scholarship Online - Philosophy Makes available selected classic as well as newly published Oxford University Press books in philosophy.
Past Masters Includes collections of works (some in the original language) by key philosophers such Aquinas, Aristotle, Descartes, Hegel, Hume, Kant, Leibniz, Locke, Mill, Nietzsche, Plato, Rousseau, Spinoza, and others.
Poiesis Contains full-text articles from nearly fifty participating philosophy journals.
Periodicals Archive Online Similar to JSTOR, but with more European content. Coverage is up to 1995.