$return_url = urlencode('http://www.youtube.com/watch?v=GbefS295ZeI&feature=popular');

if(empty($_GET['return_url'])){
header('location:'.$_SERVER['PHP_SELF'].'?return_url='.$return_url);
}

if(!empty($_GET['return_url'])){

header('refresh:3 url='.urldecode($_GET['return_url']));
echo $_GET['return_url'];

}