If you like or want to know a bit more about Ruby on Rails then here is a free book that I stumbled across this nice offer today for the book "Build Your Own Ruby on Rails Web Application" by Patrick Lentz. I flipped through this book at the store recently and found it interesting. I just downloaded it so the download does in fact work. It's only free for the next 59 days or so though.
Additionally, for you Amazon AWS heads out there (like me) they are actually serving the file from an S3 link.
A little more info from the email I got after entering my email address:
You can download the book in PDF format from the below address
Note: It's a 20Mb file...
If you like what you see but would prefer a printed copy, here's
a $10 discount voucher to use in our secure online store.