Links to categories on the internet:
Theory and Applications of Categories
- Electronic jounrnal on category theory.
Category Theory Mailing List
Hypatia
directory of research workers in Computer Science and Pure Mathematics, and a library of their papers.
Stanford Encyclopedia of Philosophy
Abstract and Concrete Categories - The Joy of Cats (J. Ad�mek, H. Herrlich, G. E. Strecker):
Download PDF-File
TheCasters
- Videos on various topics in category theory.