I recently saw a design of a physical clock that inspired me to go about creating one using Python and Tkinter. The clock was essentially a wall of letters with lights behind that light up depending on what time it is. Without the lights the clock looks like a jumble of letters, it is only when the light is on that the relevant time is displayed.
The original clock was of a proprietary design so I set about creating one that was based more on an open source clock design that I found. That clock design I found didn't display the AM or PM of the time, so I ended up tweaking that design a little anyway.