The Book of GNS3: Build Virtual Network Labs Using Cisco, Juniper, ...
jason c. neumann
Gray Hat Python
Justin Seitz
CISCO® Networking Essentials
Troy McMillan
Black Hat Python: Python Programming for Hackers and Pentesters
Penetration Testing: A Hands-On Introduction to Hacking
Georgia Weidman
How Linux Works: What Every Superuser Should Know
Brian Ward
Wicked Cool Shell Scripts: 101 Scripts for Linux, Mac OS X, ...
dave taylor
Raspberry Pi Hacks: Tips & Tools for Making Things With the ...
Ruth Suehle & Tom Callaway
The Linux Command Line, 2nd Edition: A Complete Introduction
William E. Shotts Jr.
The Linux Command Line
Linux Firewalls: Attack Detection and Response
Michael Rash
IRC Hacks
Paul Mutton
Python Crash Course: A Hands-On, Project-Based Introduction ...
Eric Matthes
The Book of GIMP: A Complete Guide to Nearly Everything
olivier lecarme & Karine Delvare
The TCP/IP Guide: A Comprehensive, Illustrated Internet Protocols ...
Charles Kozierok
The Book of Inkscape: The Definitive Guide to the Free Graphics ...
dmitry kirsanov
The Linux Programming Interface: A Linux and Unix System Programming ...
michael kerrisk
The Artist's Guide to GIMP: Creative Techniques for Photographers, ...
Michael J. Hammel
Microsoft Windows Networking Essentials
Darril Gibson
Reversing: Secrets of Reverse Engineering
Eldad Eilam
Perl Hacks: Tips & Tools for Programming, Debugging, and Surviving
Chromatic & Damian Conway & Curtis 'Ovid' Poe