I recently came across this by accident when I was looking for security software for Linux and I think this is brilliant. What I am talking about is Home Internet Security From OpenDNS which is now part of Cisco. You have the option of three packages here with the first two being completely free. I currently use OpenDNS Home where you have to register but after that it's still completely free.
Moreover please note that this is not an Anti-virus or Anti-malware program. Once configured which is actually quite easy to do this package will block numerous unwanted web content, provide you with built in fraud and phishing protection and thus protecting your identity, and much more.
What's more is that this will work on any system or computing device you use whether it be Windows, Linux, Android, Apple or whatever; handy if you don't want to much around for a while with the terminal in Linux or install any filtering software on Windows.
I seriously recommend checking this utility out.