Nixie tubes, otherwise known as numicators, were hawt stuff back in the pre-LED/LCD 60s if you wanted to display numerals in their digital form. Now do-it-yourselfers are creating retro clocks using the things. We've seen lots of nixie clocks before, but this one is the Mother of All Nixie Clocks, using 103 tubes and taking the guy seven years to build.
All of the electronic functions necessary for this display are based on tubes, no integrated circuits, no silicon at all. Amazing.