DZone.com: Zend Application demystified
While using single components of Zend Framework is as simple as including the source files, the MVC machine is quite more difficult to set up and the approach of organizing the boostrap via reusable, segregated application resources lets you manage the process without screaming for its complexity. However, it's not so simple to get Zend_Application to work the first time, and here's a primer on how it can help you.
He talks about how Zend_Application supports different environments (like testing or production) and what a resource is and how it works with the component. He shows a few examples with application.ini files that define the settings the Zend_Application should generate with and some sample code showing how to create a custom resource.