Including flood control:

Code:
on *:TEXT:!countdown:#: {
  if (%countdown.flud) { return }
  set -u30 %countdown.flud On
  msg # $duration($calc($ctime(Nov 11 2007) - $ctime))
}


Note that you can also include a specific time, such as midnight:

Code:
on *:TEXT:!countdown:#: {
  if (%countdown.flud) { return }
  set -u30 %countdown.flud On
  msg # $duration($calc($ctime(Nov 11 2007 0:00) - $ctime))
}


That will give you more accurate time.

Also, you can choose to get $DateXpander or datediff as those will show months rather than just weeks in the output. $DateXpander can be found on mircscripts.org. There are examples of how to use it for a countdown. datediff is easier for countdowns, but doesn't consider leap years afaik. Obviously, you don't need to worry about leap years for such a short duration, though.