Most of these are technical in nature, but great to see overall.

 

https://www.isc2.org/

https://www.youtube.com/watch?v=t-bjhu2z9wE

http://tldp.org/LDP/Bash-Beginners-Guide/html/

http://www.bleepingcomputer.com/

https://www.youtube.com/watch?v=GLO9HGDwOY0

http://www.darkreading.com/

http://skilldrick.github.io/easy6502/#snake

https://www.ethicalhacker.net/forums/viewtopic.php?f=90&t=11757#p62170

https://members.elearnsecurity.com/

http://proactivedefender.blogspot.com/2012/06/esxi-security-lab.html

https://www.exploit-db.com/

http://www.fuzzysecurity.com/tutorials.html

http://www.fuzzysecurity.com/tutorials/16.html

http://www.hackthissite.org/

http://null-byte.wonderhowto.com/how-to/hack-like-pro-reconnaissance-with-recon-ng-part-1-getting-started-0169854/

https://howsecureismypassword.net/

http://www.smallnetbuilder.com/wireless/wireless-howto/31914-how-to-crack-wpa-wpa2-2012?start=2

https://community.rapid7.com/docs/DOC-2196

http://kaoticcreations.blogspot.com/2011/08/automated-lfirfi-scanning-exploiting.html

https://evilzone.org/tutorials/local-file-inclusion-(lfi)/

http://www.offensive-security.com/metasploit-unleashed/Main_Page

https://www.microsoft.com/en-gb/security/pc-security/password-checker.aspx

https://sathisharthars.wordpress.com/2015/01/28/oscp-offensive-security-certified-professional-handy-tips-and-tricks/

http://www.0daysecurity.com/penetration-testing/enumeration.html

http://www.enigmagroup.org/exploits

https://myoscp.wordpress.com/2013/05/28/preparation-to-my-oscp/

http://www.pentest-standard.org/index.php/PTES_Technical_Guidelines

http://www.securitytube.net/

http://blog.netinfiltration.com/2013/12/03/setting-up-a-pentest-lab-for-beginners/

http://www.projectshellcode.com/?q=node/12

http://null-byte.wonderhowto.com/how-to/hack-like-pro-spear-phish-with-social-engineering-toolkit-set-backtrack-0148571/

http://docs.python.org/2/tutorial/

https://www.virustotal.com/en/

https://www.exploit-db.com/papers/12902/

https://www.vulnhub.com/

http://opensecuritytraining.info/Welcome.html

https://www.exploit-db.com/exploits/25912/

https://zerodium.com/