Looking for a PHP templating system

Does anybody have any suggestions for good PHP-based templating systems? I want to start abstracting my code from the HTML itself. I thought about creating my own, but I might as well ask before I reinvent the wheel. Here's some ideas that I came up with that I wanted the system to have: * Simple if/else conditions * Simple loops (foreach? while?) * HTML "blocks" (Basically creating a tag or something of that nature that will hold a large chunk of HTML with the ability to insert content or variables in a defined location) * Simple enough that I can hand a list of variables to a design guy and he could catch on pretty quickly -Isaac