If only we can have a huge wall like China's Bastille Linux is one way to harden your system but adding a kernel-level hardening scheme pushes it a notch higher. This is where LinuxSecurity.com comes in with a short tutorial on how to patch your kernel and have a really hardened Linux installation.to protect us from security breaches, then we'd all be sleeping soundly every night. Unfortunately, there isn't one available but we can always try to prevent breaches by hardening our computer system.
Word of warning, though, you need to be comfortable tweaking your kernel settings before you attempt doing this.
Image from Flickr:Mckaysavage.