Adam Jacobs is a Founder of HJK Solutions which helps startups build stable, scalable, and repeatable infrastructures utilizing open-source tools

one of the tools they use is Puppet.

http://reductivelabs.com/trac/puppet/wiki/AboutPuppet

"Rather than approaching server management by automating current techniques, Puppet reframes the problem by providing a language to express the relationships between servers, the services they provide, and the primitive objects that compose those services. Rather than handling the detail of how to achieve a certain configuration or provide a given service, Puppet users can simply express their desired configuration using the abstractions they're used to handling, like service and node, and Puppet is responsible for either achieving the configuration or providing the user enough information to fix any encountered problems."

Building a plugin for this that will generate a dot file that can then be pumped though graphviz - to product a diagram of what the servers are and how they are connected  could be good fun