"What is the book that changed your life? (not novels or religious texts)"
I think it's a wonderful way to connect in a less superficial way and learn a little more about each other. It's also a wonderful way to discover new books worth reading.
This is one of them (the full list is here):
“Our new reality is zero-day, APT, and state-sponsored attacks. Today, more than ever, security professionals need to get into the hacker’s mind, methods, and toolbox to successfully deter such relentless assaults. This edition brings readers abreast with the latest attack vectors and arms them for these continually evolving threats.” --Brett Wahlin, CSO, Sony Network Entertainment “Stop taking punches--let’s change the game; it’s time for a paradigm shift in the way we secure our networks, and Hacking Exposed 7 is the playbook for bringing pain to our adversaries.” --Shawn Henry, former Executive Assistant Director, FBI Bolster your system’s security and defeat the tools and tactics of cyber-criminals with expert advice and defense strategies from the world-renowned Hacking Exposed team. Case studies expose the hacker’s latest devious methods and illustrate field-tested remedies. Find out how to block infrastructure hacks, minimize advanced persistent threats, neutralize malicious code, secure web and database applications, and fortify UNIX networks. Hacking Exposed 7: Network Security Secrets & Solutions contains all-new visual maps and a comprehensive “countermeasures cookbook.” Obstruct APTs and web-based meta-exploits Defend against UNIX-based root access and buffer overflow hacks Block SQL injection, spear phishing, and embedded-code attacks Detect and terminate rootkits, Trojans, bots, worms, and malware Lock down remote access using smartcards and hardware tokens Protect 802.11 WLANs with multilayered encryption and gateways Plug holes in VoIP, social networking, cloud, and Web 2.0 services Learn about the latest iPhone and Android attacks and how to protect yourself