There was a brief period through the 1960s into the 1970s when the last word in electronics was the calculator. New models sold for hundreds of dollars, and owning one made you very special indeed.

There are a few very rare and very expensive calculators with Nixie tube displays scattered about calculator history, but so far we haven’t seen someone build a truly useful Nixie calculator ...

Every detail, down to the white lines along the top and bottom of the watch face, projects retro-modern calculator style." It's just $36, too, cheap enough for me not to beg for smartwatch features.