The Plotclock is a robotic clock that writes the time on a whiteboard with a marker. We have seen it built with Arduino in the past. As it turns out, someone has built a steampunk version of it that happens to be wearable like a watch.
More like this ➡️ here
It is not exactly the most compact unit, so wearing it around may not be convenient. It might me an idea worth trying at geeky parties though.
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