Tor Books is offering free e-books in PDF or HTML format for a limited time. You can read the books through your readers, laptop, computer, mobiles and smartphones, including the iPhone.
Tor.com is a site for news and discussion on science fiction, fantasy topics and is a joint effort of Tor Books and Macmillan group of publishers.
For a limited time, Tor.com offers
24 free e-books from major authors and artists in PDF and HTML formats including high resolution cover arts and you can download it at this link.
You can read this book in any devices such as Amazon’s Kindle, Sony Reader, iPhone, laptops, computers and mobiles.
You can also get a free e-book once every week, if you join their mail subscription. I have one of those, but I am not sure whether they are still offering it now. I will double check and add that link here later.
Cnet.com said that Tor.com is still in beta stage and they may provide more free e-books in the near future.
You can also check out
Baen Books for more free e-books.