Journals from the APS (Browsable anywhere; downloads available at libraries only)

Genealogical research, with digitized images of the U.S. Federal Census from 1790 forward, the American Genealogical Biographical Index, Passenger, and Immigration Lists Index, and more.  (Link opens in a new tab/window.)

Job Search tools plus details on businesses and households within the U.S.  (Link opens in a new tab/window.)