Nixie tubes + concrete block = cool clock

Check out Norwegian maker Hans Jørgen Grimstad’s concrete & nixie clock. (The video shows some sort of test, not the regular clock operation.) Hans’s website is in Norwegian, and Google Translate doesn’t savvy Norwegian very well, so its operation is somewhat mysterious. However, I do see that there’s an XBee involved. Hans, would you care to share some details? [Thanks, Hellgeir]