They give away one book per day. They don't send an email, but I have a script that scrape their site and send myself an email. I'm happy to add to a mailing list if there's interest.
Thanks for the tip. I just implemented it and it said 44 other people are monitoring that page haha.
Just a thought.. instead of building something that sends out an email... it would be much more convenient to build something that automatically adds each new book to your account.. using something like Python's Selenium library to do it.