Answers.com [ http://www.answers.com/ ]
The ultimate answer engine, with quick accurate dictionary, thesaurus, encyclopedia, bios, tech terms, news, sports, weather, and much more.

Probert Encyclopaedia [ http://www.probertencyclopaedia.com/ ]
A free online encyclopedia of over 300,000 cross-referenced and interlinked references and 15,000 illustrations, specialising in topics omitted by other encyclopedias.