The American Chemical Society: http://portal.acs.org/portal/acs/corg/content
Periodic Table of the Elements: http://www.webelements.com/
American Chemical Society Division of Chemical Education: http://www.divched.org/
Boston Region Inorganic Chemists: http://www.uvm.org/bric/
Council of Undergraduate Research: http://www.cur.org/
Sigma Xi: http://www.sigmaxi.org/