Get Magento Configurations as XML

config.php

<?php
/*
Put this file to /magento/shell/config.php and run

$ php shell/config.php | tidy -xml -i > config.xml

*/

require_once 'abstract.php';

class Export_Config extends Mage_Shell_Abstract
{
    public function run()
    {
                $config = new Mage_Core_Model_Config();
                $config = $config->loadBase();
                $config = $config->loadModules();
                $config = $config->loadDb();
                echo "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n";
                echo $config->getXmlString()."\n";
    }
}

$shell = new Export_Config();
$shell->run();