Hey, look! I made a clock! The Apple Watch is now obsolete.
I am learning how to use the D3.js library to do data visualizations. It doesn't really make sense to consider hour, minute, and second as data to be "visualized", but this was a simple exercise to learn how to create graphical elements and animate them as the data changes.
If you're interested, you can click the JavaScript, CSS, and HTML links at the top to see exactly how it is implemented. (Note that JSFiddle is magically importing the D3 library, so you don't see that in the HTML.)
Here is another way to view the clock along with its source: http://bl.ocks.org/kristopherjohnson/1db0d39a9ed54d224ee7