<?php
    private function LatLngDist($p, $q) {
        $R = 6371; // Earth radius in km

        $dLat = (($q[0] - $p[0]) * pi() / 180);
        $dLon = (($q[1] - $p[1]) * pi() / 180);
        $a = sin($dLat / 2) * sin($dLat / 2) +
                cos($p[0] * pi() / 180) * cos($q[0] * pi() / 180) *
                sin($dLon / 2) * sin($dLon / 2);
        $c = 2 * atan2(sqrt($a), sqrt(1 - $a));

        return $R * $c;
    }

<?
$rewrite['/'] = 'Новый тайтл';
$rewrite['/about/'] = 'Новый тайтл';

ob_start("titler");

function titler($content) {
    global $rewrite;
    if (isset($rewrite[$_SERVER['REQUEST_URI']]))
        return preg_replace("#<title>.*?</title>#",'<title>' . $rewrite[$_SERVER['REQUEST_URI']] . '</title>');
    else return $content;
}