if you are looking at longer more complex "redirects" I would suggest not using includes, or if you are, then do sometihng like...
<?php
switch ($page)
{
case 'realaudio';
$_GET['styles'] = $styles;
include 'realaudio.php';
break;
default:
include 'home.php';
}
?>
and have your included files setup to parse your $GET vars... (I cant gaurantuee that $GET is writable but I know for afact that $_POST is writable.... considering one is, I would assume all are