In a new post to the Zend Developer Zone, Brett Zamir has posted a new tutorial that talks about using the Smarty templating system to create what he calls the HYSOCAMTT templating approach ("Have-Your-Separation-Of-Concerns-And-Mix-Them-Too".
This article aims to highlight a approach which allows one to separate everything from one's business logic to one's design logic, to XHTML from CSS, one's Javascript from the page structure, etc., while at the same time being able to be lazy and include, for example, CSS information within the same document (template) as one's XHTML
The tutorial uses an extension for Smarty called SmartyDocB that makes the documentation side much easier. He works through the templating process and includes some of the code for the .tpl files to get you started.
He also includes some future goals for his idea, a mention of XSL templating, XQuery and the potential for templating across programming languages to make your site even more flexible.