If you enjoy sci-fi, Tor Books gives a free novel in epub and mobi formats each month or so; just sign up for the e-newsletter. This is literally the reason I'

If you enjoy sci-fi, Tor Books gives a free novel in epub and mobi formats each month or so; just sign up for the e-newsletter. This is literally the reason I'm excited to learn about nov.el and other epub readers; when I get an epub book, I sigh inwardly because there's 2-3 more steps to go before I can actually read it, e.g. email the file to my kindle address, wait for Amzn to ask me to verify it's not spam, then finally download it to my Kindle.