LibriVox: free audio files of public fomain books read by volunteers.

http://digital.library.upenn.edu/books/ 25,000 free books includes history, science, social science, geography, law and more.

http://www.gutenberg.org/ There are 17,000 free <http://www.gutenberg.org/freedom> books in the Project Gutenberg Online Book Catalog <http://www.gutenberg.org/catalog/>.

http://www.freebooks4doctors.com/ Free online books for medical practitioners.

http://www.e-book.com.au/freebooks.htm Books in the Public Domain and other free books. Includes links to classic works of literature, science and other subjects.

http://www.schoolzone.co.uk/ Resources - all free! We ask UK teachers to write *independent reviews and evaluations* of teaching and learning materials: over 50,000 so far! Plus articles, research reports and more