"Countdown" is merely a countdown timer with a graphical interface for Mac OS
X.  You set a time interval in minutes, press "start", and it counts down until
the set time runs out. It shows the remaining minutes in the application icon
(both when you press Cmd-Tab and in the Dock).  You can stop the timer at any
time during the countdown.  "Countdown" features a global shortcut key to
activate the countdown: Ctrl-Opt-Cmd-k .  Its user interface is absolutely
elementary because I did this app so that it just fits my needs.