This simple extension for Twig (the template language made by fabpot) allows you to use a filter "markdown" that converts text to HTML given the markdown ruleset.
The code is based on PHP Markdown by Michel Fortin (http://michelf.com/projects/php-markdown/), kudos to him !
If you want to test it, just add Twig's code in the root directory with the name "Twig" and access the Example/index.php script with your LAMP (or whatever) websever !
For any questions or remarks, please contact me at: pmallet[at]clever-age[dot]com