Architecture Playbook : This playbook is targeted on providing practical tools for creating your IT architecture or design faster and better. This book contains architecture ...
OWASP : The Open Web Application Security Project (OWASP) is a worldwide not-for-profit charitable organization focused on improving the security of software.
Inj3ct0r 1337day.com : Exploit database separated by exploit type (local, remote, DoS, Poc, etc.)
Pro Git : The entire Pro Git book, written by Scott Chacon and published by Apress, is available here