The Zend Developer Zone has a new tutorial by Vikram Vaswani talking about the use of the HTML_Template_Flexy templating system in your application.

There's no shortage of PHP-based template engines out there: Smarty, Template_IT, Xipe and patTemplate are just some of the names that spring to mind. [...] As you'll shortly see, although Flexy isn't as feature-rich or as well-documented as some of the other options available, it's lightweight, fast and comes with some unique features that will endear it to most developers.

He shows the creation of a simple template file, a plain text file that has the tags for the search and replace the templating framework does to inject the application's information. He also shows a few more complex things like object mapping, conditional structures, output of sets of data and the built-in forum helper technology. He also briefly mentions some of the configuration settings the templating software makes available.