It's a good idea to "hide" PHP anyway so you can write a RESTful web application.

Using Apache Mod Rewrite:

RewriteEngine On
RewriteRule ^control/([^/]+)/(.*)$ sitecontroller.php?control=$1&query=$2

You then use a function like the following as a way to retrieve data (in a zero indexed fashion) from the $_GET superglobal.

<?php
function myGET() {
  $aGet = array();

  if(isset($_GET['query'])) {
    $aGet = explode('/', $_GET['query']);
  }

  return $aGet;
}
?>

This is only a really basic example of course - you can do a lot with Mod Rewrite and a custom 'GET' function.