I've been a fan of Kurt Grigg and the unique things he creates with javascript.
Two of my favorites are the Clock and the 24 hour or Military clock.
With his permission I have created two html application files ( .hta ) files which
will run in a small window on your desktop as shown in the two actual size images below.

Desktop javascript Clock  24 hour Military javascript Clock

If you would like a copy, right click the links below, and select Save As and then save them
to your desktop. Note: if you left click either link you will have to click yes to run the file.
However they will open and run when left clicked.

Clock   24 Hour Clock