public static function Clean($Mixed) {
       if (!is_string($Mixed)) return self::To($Mixed, 'Clean');
       $Mixed = strtr($Mixed, self::$_CleanChars);
       $Mixed = preg_replace('/[^A-Za-z0-9 ]/', '', urldecode($Mixed));
       $Mixed = preg_replace('/ +/', '-', trim($Mixed));
       return strtolower($Mixed);
   }