Ask an Expert. Lists of experts by subject and links to other "expert pages".
AllExperts. Read the expertise of the visiting scholars and choose one to answer your question.
Radio's Dr. Science. Humorous answers.
Ask A Scientist. An archive and a search engine of hundreds of questions answered by Argonne National Lab.
Usenet's FAQ's, by a newsgroup that you can join.
Science Matters. Relativity, particles, cosmology, and other modern physics.
Mad Scientist answers questions in humorous way.
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