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GitHub User: baweaver
Pssst: sed 's/speces/spaces/g'
I'd suggest fairly strongly getting a nice deep familiarity with SSH and how it works.
There's a lot you can do between that and some sage knowledge on the sudo command to write a fairly well locked down server that's ready to rock the world.
Combine this with knowledge on OpenBSD and how it works and you have a tank of a server that's going to be near impossible to break into.
SSH Mastery: http://www.amazon.com/SSH-Mastery-OpenSSH-Tunnels-ebook/dp/B006ZO9ULK
Absolute OpenBSD: http://www.amazon.com/Absolute-OpenBSD-Practical-Paranoid-ebook/dp/B00CH96VB4/ref=sr_1_1?s=digital-text&ie=UTF8&qid=1368591922&sr=1-1&keywords=absolute+openbsd