Quick and dirty way to do it:
Code:
<?
$urls = file('URLS.txt', FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES)
$url = array_shift($urls);
array_push($urls,$url);
file_put_contents('URLS.txt',implode("\r\n",$urls));
header('Location:'.$url);
?>
Will work. Untested, don't ask for me to fix it if it doesn't kick - pay woj instead.