A cool little 20 Hour Timer!
Simple to use, no settings, just click start for a countdown timer of 20 Hours.
Try the Fullscreen button in classrooms and meetings :-)

Here are some great pre-set timers ready to use. They range from a 1 second timer - up to a year timer! It's pointless - but you asked for it! :-)
Remember! If the timer you want is not here -- just make ANY timer you want above. Simple!