Barnes & Noble has updated a number of their B&N Classics Series books -- they are now in the EPUB format rather than PDB (ereader), which means they should work on all the nook ereaders, not just the original nook. Right now, 20 of the titles are free. These are annotated classics, not just scanned editions, which usually sell for $3-$4.
- Wuthering Heights, by Emily Bronte
- Twenty Thousand Leagues Under the Sea, by Jules Verne
- Three Musketeers, by Alexandre Dumas
- Good Soldier, by Ford M Ford
- Awakening and Selected Short Fiction, by Kate Chopin
- Art of War, by Sun Tzu
- Tale of Two Cities, by Charles Dickens
- Complete Sherlock Holmes, Volume I, by Sir Arthur C Doyle
- Scarlet Letter, by Nathaniel Hawthorne
- Portrait of the Artist as a Young Man and Dubliners, by James Joyce
- Paradise Lost, by John Milton
- Jude the Obscure, by Thomas Hardy
- Jane Eyre, by Charlotte Bronte
- House of Mirth, by Edith Wharton
- Gulliver's Travels, by Jonathan Swift
- Collected Poems, by Emily Dickinson
- Don Quixote, by Miguel de Cervantes
- Adventures of Tom Sawyer, by Mark Twain
- Picture of Dorian Gray, by Oscar Wilde
- Odyssey, by Homer