Finally an accurate binary clock that is using new DS3231 RTC chip. This is the only clock I have that keeps very accurate time without being connected to the internet. Given that it uses a real DS3231 chip that costs over $10 in moderate quantity this shield is good value. I love the neo-pixels used, I can customize the colours for hours, minutes and seconds plus change them based on time of day or room light.
That this is open-source for both the hardware and software makes this a great shield. I've ported the software to run on an ESP32 based Arduino UNO board to add even more functionality such as changing the display colours to indicate the current weather and to integrate with my home automation system.
I was so impressed with this shield that I bought a second one for my office.
I'm very pleased with my "useless nixie device" :) I was looking for something pretty rather than useful (like a nixie clock for example) and this fits the bill nicely. It will have pride of place on my desk at work soon. The instructions for the main kit were the most detailed I've seen for any kit, very easy to follow. However I couldn't find any instructions for the nixie adaptor that connects the nixie tube to the main kit. I ended up finding some pictures online and guessing my way there.