From Wooji Juice:
Voluminous finds free, public-domain books on the Internet, downloads them, formats them for easier reading, and manages the collection. Offering more than 25,000 books, including many famous plays, novels, poetry and reference works, new titles are added to the catalogue regularly. Voluminous also includes a variety of ways to pick out the titles you want: search by title or author instantly, or browse the topic catalogue, based on the Library of Congress classification scheme.
What's new in this version:
Snow Leopard compatibility update