Apress is offering free ebooks online. This is not a limited time offer. You can find out more about it on their site.
Preliminarily, here are some of the offerings that I found:
- TouchDevelop 3rd Edition
- Managing Risk and Information Security
- Intel® Xeon Phi™ Coprocessor Architecture and Tools
- Intel® Trusted Execution Technology for Server Platforms
- Building the Infrastructure for Cloud Security
I downloaded two that were not listed on their ApressOpen home page: