I have had a few people ask me this very question recently, so i decided to post my source for information on securing boxes, and some applications...
If you have questions, ask
But yes, you guys have heard of that NSA agency thingie, right? Well, it just so happens that they write some of the most amazing and paranoid guides to securing boxes...:
Security Configuration Guides
Enjoy, most are quite a read

----------------
Microsoft, the leader in using innovative tactics to promote irksome experience, coupled with antiquated technology that's held together by a pyramid of makeshift afterthoughts.
Apple, the leader in using irksome tactics to promote innovative experience, coupled with an antiquated core that's enhanced by state-of-the-art afterthoughts.
Linux, the leader in not using any tactics to promote user-defined experience, coupled with state-of-the-art core enhanced by innovative afterthoughts.
