The Driftwood Binary Clock
We'll be the first group of people to admit that there are an almost infinite number of Arduino-based clock projects out there - and a fair few of them can be somewhat confused for each other.
However this clock by Matt Wos is both interesting and can be constructed by anyone with some basic electronics experience. Matt has created a binary display clock using "NeoPixel" style WS2812B RGB LED button PCBs, which are mounted on an open wire frame.
Apart from telling the time in binary fashion, there is also an alarm and an infra-red remote control - with the entire clock being embedded into a piece of driftwood. You can only agree that this is a fascinating and very clever piece of work:
All the required information and code are provided, so for more information on how to make your stylophone, visit the detailed project page.
And if you're interested in doing this yourself, PMD Way can help you with the parts, such as: