• Wowio - Public domain, free legitimate copyrighted materials & one of the only with a selection of Comic Books
• BizBooktalk - Free book giveaway contests on Fridays
• SwapThing - Community of users who swap items including books
• BookCart - Internet paperback exchange  
• SF-Books - Exchange Sci-Fi Books here
• PaperbackSwap - Swap books for free
• MoochMuch - Organize your book lending with your friends
• CHMPDF - A collection of general interest and technical e-books 
• LibraryElf - The perfect companion to a public library system
• Scribd - Open library to publish and discover documents online
• Online Books Page - Facilitates access to books that are freely readable over the Internet 
• Podiobooks - Free audio books that you can subscribe to with iTunes or any other pod catcher
• BookRags - Research material in the form of eBooks
• Technical Books Online - Old tech books from the “vacuum tube age” of electronics
• Word Public Library - PDF ebooks for download
• Free Tech Books - Free computer science and engineering books
• Gutenberg Project Top 100 - Popular books from the oldest producer of free ebooks on the Internet
• BookMooch - Community for exchanging used books
• ebookSpyder - Specializes in technical books ranging anywhere from C# to AJAX
• Google Book Search - Read the classics online
• Dwalin - Plain text novels
• Free Computer Books - Technical resources about computers
• Librivox - Audio works and podcasts of books  
• CliffsNotes - Get the notes to cram for the exam
• WIkibooks - Free textbooks
• DailyLit - Receive small parts of books via email
• ManyBooks - Free eBooks for your PDA, iPod, or eBook reader
• BookCrossing - Where real books are released into the wild to be found by others
• Bookins - Swap real books with other readers
• WellToldTales - Free short story podcasts (like audio books, but shorter)
• Realtime Publishers - free IT eBooks by many of the world’s best authors
• FrugalReader - Trade Books for free
• TitleTrader - Swap books, movies, and music
• ZunaFish - Trade your old media and books items for new titles you’d rather have
• SwapSimple - Swap your used books here  
• PinkMonkey - Study Guides
• eBookWorld - Technical resources
• Flaxx - IT and computer books
• Baen Library - Free science fiction and fantasy novels
• LibraryThing - Social networking and free books
• ebookSearchr - Google powered
• Internet Archive - The Internet indexed - that includes a vast text library
• BookYards - Books, videos, education materials
• Memoware - Free books for your PDA

 Wow, looks like you've been doing some research! Thanks.

 Oh, of course... you were looking for cookbooks! I would never have guessed it. LOL

 That's my story and I'm sticking to it!  LOL

 What a great list! Just as an FYI, Project Gutenberg has two spin-off sites which have even more titles. The US has very restrictive public domain laws and many things are public domain elsewhere but not yet in the US. Project Gutenberg of Australia was started to showcase Australian content and offer a home for some of these items (their laws pass something into the public domain 75 years after the death of the author). Project Gutenberg of Canada highlights Canadian content and works which pass into the public domain 50 years after the death of the author. I am very interested in the area of copyright reform and the public domain, and keep regular tabs on sites like these :) Links:

• http://www.gutenberg.net.au/
• http://gutenberg.ca/ 

I'm a member of paperbackswap.com. I love it!

I don't usually get books until I have checked them out from the library and have decided that I'd like to have it on my shelf for reference.
 

 Another source is Arcamax

You can either read them online or they'll email them to you a chapter a day. You'll receive some spam from them, but not much, not enough to be concerned about. They have a list especially for kids, too.  

 Wow! What a treasure trove!