Spotted this while faffing around duplicating a Rails install.

It's similar to Puppet in that it allows you to deploy a similarly configured server based on a template. However, the really cool part is that you can build a template from an existing server without a lot of faffing. You can also use it to build the templates in formats Chef and Puppet can use.

Blueprint
https://github.com/devstructure/blueprint

Works on Red Hat and Debian based OS only, according to the docs.