function memory () {
    $s = $this->grab_key('hw.physmem');

    if (PHP_OS == 'FreeBSD' || PHP_OS == 'OpenBSD') {
      // vmstat on fbsd 4.4 or greater outputs kbytes not hw.pagesize
      // I should probably add some version checking here, but for now
      // we only support fbsd 4.4
      $pagesize = 1024;
    } else {
      $pagesize = $this->grab_key('hw.pagesize');
    } 

    $results['ram'] = array();

    $pstat = execute_program('vmstat');
    $lines = split("\n", $pstat);
    for ($i = 0, $max = sizeof($lines); $i < $max; $i++) {
      $ar_buf = preg_split("/\s+/", $lines[$i], 19);

      if ($i == 2) {
        $results['ram']['free'] = $ar_buf[5] * $pagesize / 1024;
      } 
    } 

    $results['ram']['total'] = $s / 1024;
    $results['ram']['shared'] = 0;
    $results['ram']['buffers'] = 0;
    $results['ram']['used'] = $results['ram']['total'] - $results['ram']['free'];
    $results['ram']['cached'] = 0;
    $results['ram']['t_used'] = $results['ram']['used'];
    $results['ram']['t_free'] = $results['ram']['free'];

    $results['ram']['percent'] = round(($results['ram']['used'] * 100) / $results['ram']['total']);

    if (PHP_OS == 'OpenBSD') {
      $pstat = execute_program('swapctl', '-l -k');
    } else {
      $pstat = execute_program('swapinfo', '-k');
    } 

    $lines = split("\n", $pstat);

    $results['swap']['total'] = 0;
    $results['swap']['used'] = 0;
    $results['swap']['free'] = 0;

    for ($i = 0, $max = sizeof($lines); $i < $max; $i++) {
      $ar_buf = preg_split("/\s+/", $lines[$i], 6);

      if ($ar_buf[0] != 'Total') {
        $results['swap']['total'] = $results['swap']['total'] + $ar_buf[1];
        $results['swap']['used'] = $results['swap']['used'] + $ar_buf[2];
        $results['swap']['free'] = $results['swap']['free'] + $ar_buf[3];
      } 
    } 
    $results['swap']['percent'] = round(($results['swap']['used'] * 100) / $results['swap']['total']);

    return $results;
  }