Squirrels + Ansible == Awesome
This article came across my twitter feed earlier today and its a really good discussion of the value of version control of your configuration management.
The big take away for me to remind people that NOT having automation for setting up systems is just asking for disaster.
I happen to really like Ansible because of the pretty short learning curve (and it can handle really complex configurations), but Puppet, Chef, and SaltStack are also excellent options.