// show online member names
    function getOnlineMemberNames() {
        $db     =& JFactory::getDBO();
        $result = null;

        $query = 'SELECT DISTINCT a.userid' .
                 ' FROM #__session AS a' .
                 ' WHERE client_id = 0' .
                 ' AND a.guest = 0';
        $db->setQuery($query);
        $result = $db->loadObjectList();

        if ($db->getErrorNum()) {
            JError::raiseWarning( 500, $db->stderr() );
        }

        return $result;
    }