The Web offers a number of encyclopedias and reference books:
Center for History and New Media:
Tools: http://chnm.gmu.edu/tools/index.php and
Resources: http://chnm.gmu.edu/resources/index.php
Echo:History of Science, Technology and Industry
http://echo.gmu.edu/index.php
Encyclopedia of Educational Technology (EET) is a collection of short multimedia articles on a variety of topics related to the fields of instructional design and education and training. http://coe.sdsu.edu/eet
Hurricane Digital Memory Bank: http://hurricanearchive.org/
Internet Modern History Sourcebook: Primary sourcebook intended to serve the needs of teachers and students in college survey courses. http://www.fordham.edu/halsall/mod/modsbook.html Internet Encyclopedia of Philosophy
Internet Encyclopedia of Philosophy: http://www.iep.utm.edu/
Multidisciplinary Resources (including Encyclopaedias and Reference Titles http://www.jisc.ac.uk/index.cfm?name=coll_subject_m
WWW Virtual Library: http://vlib.org/