Free Online Books Directory

Project Gutenberg was to be the best online book project, but didn't live up to the hype, but has over 13,000 titles from The Online Books Page.

Librivox - volunteer, open source project provides free audiobooks from the public domain (mp3, ogg)

Google Books - classic public domain books scanned to PDF format. Search the full text of books.

Freebook Sifter - lists 35,000 free eBooks on Amazon.com by category.

Bartleby reference books - great books online

Our Roots - Canada's local history

University of Pennsylvania digital library has over 20,000 free books online:

The Internet Public Library
Online Texts [Subject Collections > Arts and Humanities > Literature]

"Online Literature Library" - collection of classics

University of Texas (Austin) Online Library - many books are limited to UT Austin students

Math.Gatech.Edu - math textbooks from Georgia Institute of Technology

Arxiv.Org - Articles on astrophysics, relativity, quantum cosmology, high energy physics from Cornell University

55 Ways to Have Fun with Google -by Philipp Lenssen http://googleblog.blogspot.com/2006/09/55-ways-to-have-fun-with-google.html.

The Internet Archive

Fictionwise

eBook Mall

Aesop Fables

bibliomania: Chekhov, Wilde

WorldWideSchool.org: classics

The Creative Commons - novels, photos, media, music

NetGuide Best of the Web Reviews - searchable digital library

National Academy Press -searchable, 3000 publications (free)

The Invisible Web - libraries, databases

World Wide Web Virtual Library - maintained by volunteers

SEE ALSO:

PDQ: "Deep Web" - vast reservoir of information missed by most web searches, far larger than the Web we are more familiar with.
PDQ: Search - links to Web search services and directories.