Project Gutenberg offers full text for nearly 60,000 free eBooks. Choose among free epub books, free kindle books, download them or read them online. The books have been digitized and proofread by volunteers, for enjoyment and education. The collection consists of books that are in the public domain (primarlially books before 1923 in the US). Most books are in English, but books are avalable in many other languages, with particularly large collections in Spanish and Chinese.
HathiTrust Digital Library is a digital preservation repository and highly functional access platform. It provides long-term preservation and access services for public domain and in copyright content from a variety of sources, including Google, the Internet Archive, Microsoft, and in-house partner institution initiatives. While many of the site's features and much of its content is not available to the CSI community; anyone can search the catalog, see samples from full text documents, and see a number of freely available documents.
Digitized materials from the extensive archival collections of the US Library of Congress. Topics cover all of American history and collections are searchable and browse-able. Most collections have contextual and contents information (finding aids). Includes content formerly in the American Memory website.