Wanted Plugin: Countdown / Alarm

[Filb]

I know the "uptime" plugin features a "Timer", but it's not what I'm looking for.
I'd like a plugin that would allow me to set a certain date & time and then it would show the remaining time within the launch bar. The time format should be possible to customize.

Example: "$d days, $h hours, $m minutes, $s seconds" should output something like "2 days, 0 hours, 25 minutes, 58 seconds". It should also be possible to use a compact format like "$d:$h:$m:$s" etc.

When the countdown is down to zero, it should be possible to display a big alarm message (always on top) on the screen, run a custom application, or play a sound, etc.

If there's already a plugin with this functionality, let me know.
Otherwise, it would be great if someone made one like this.