public static function Urls($Type = NULL) {
      static $Urls = NULL;

      if ($Urls === NULL) {
         $Urls = array('' => Asset('/uploads', TRUE));
         
         $Sender = new stdClass();
         $Sender->Returns = array();
         $Sender->EventArguments = array();
         $Sender->EventArguments['Urls'] =& $Urls;

         Gdn::PluginManager()->CallEventHandlers($Sender, 'Gdn_Upload', 'GetUrls');
      }

      if ($Type === NULL)
         return $Urls;
      if (isset($Urls[$Type]))
         return $Urls[$Type];
      return FALSE;
   }