A brief note to point out that the World eBook Fair (October, 2006) began today. The fair provides FREE full access to over 500,000 eBooks all in PDF.
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Keyword search or browse:
http://worldebookfair.com/Collections.htm
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and more than 5000 books (mainly from Project Gutenberg) for dowload to mobile devices.

For everyone’s info, we at Bookyards (http://www.bookyards.com) have also compiled a good collection of digital libraries with books available for downloading for free. Just go to Bookyards “Library Collections – E Books” at http://www.bookyards.com/links.html?type=links&category_id=1780
There are approximately 550 digital libraries separated alphabetically and by category, with over 300,000 unique ebooks