UCCS Freethinkers Link Collection:

Here is a link to the best collection of material in the internet at Internet Infidels.

Freedom From Religion Foundation is an organization fighting for the separation of church and state.

Skeptics Society exists "for the purpose of promoting science and critical thinking, and disseminating information on pseudoscience, pseudohistory, the paranormal, magic, superstition, fringe claims and groups, revolutionary science, proto-science, and the history of science and pseudoscience."