Did you see my recent column — [Electronic] Ghosts of Christmas Past and Future — in which I reflect on how technology has evolved since I was a little lad? In those days of yore, we had a lot of interesting display technologies, many of which were electromechanical in nature. I bet if we could go back in time to circa the 1960s, they would drool over the electronic display technologies we now have at our fingertips. So, it’s a bit ironic that, since we do have incredibly sophisticated display technologies at our beck and call, so many of us are enamored with the electromechanical offerings of yesteryear. As an aside, speaking of going back in time, I’m reminded of the scene in Dirk Gently’s Holistic Detective Agency by the late, great Douglass Adams where Dirk is talking to the professor:
Dirk: “You have a time machine and you use it for… watching television?” Professor: “Well, I wouldn’t use it at all if I could get the hang of the video recorder.”
It’s sad to think that younger readers may not understand this. The thing is that the video cassette recorders (VCRs) of yesteryear — the distant ancestors of today’s digital video recorders (DVRs) — came equipped with convoluted control paradigms that were notoriously hard to wrap one’s brain around. It required someone with an advanced university degree to set the system clock to the correct time, after which you typically managed to record the wrong channel at the right time or the right channel at the wrong time. It was a rare occurrence indeed when you successfully managed to record the program you were aiming for. Ah, the good old days, but we digress… Some time ago, I wrote a column about Rolling Your Own Split Flap Displays. I love split-flap displays. I would really love to lay my hands on an array of these one day. I also love the electromectanical 7-segment displays and flip-dot displays depicted in this video.  
The reason I mention this here is that my chum Jay Dowling is constantly trying to persuade me to purchase a PRUSA 3D Printer (currently $749 as a kit or $999 fully assembled), or — failing that — a PRUSA MINI (only $349, and Jay says he thinks there’s free shipping until the end of the year). Jay raves about the quality of these little rascals, and I must admit that more and more of my hobby projects would benefit from me being able to create specialized bits and pieces. In his most recent email, Jay said, “When you do get around to purchasing a 3D printer, this may interest you.” Jay followed this with this link to the MyMiniFactory.com site from where you can download the files required to build the moving parts for a gorgeous electromechanical 7-segment display.
Printed parts for a DIY electromechanical 7-segment display (Image source: Fhuable/MyMiniFactory)
Jay also included this link, which takes you to a site where you can see the 7-segment display shown here in action.
Gorgeous electromechanical 7-segment display (Image source: Fhuable/MyMiniFactory)
As another aside, I just ran across a rather interesting video on YouTube showing how to make a mechanical 7-segment display using cardboard. This starts off looking somewhat simple, but it turns out to be far more sophisticated than you might think. Building one of these with a youngster may we;; spark an interest in mechanical engineering.  
Arrggggh! (And I mean this most sincerely). I just did a quick search on YouTube to see if I could find a video of the DIY 7-segment display that Jay pointed me to. I couldn’t, but instead I ran across this video showing a really tasty electrotechnical implementation.  
I just had a quick Google while no one was looking and discovered a company called ScoreTronics, which now produces and sells the 4″ and 6″ sizes (402L and 602L) of these little rascals (see the Brochure). What can I say? I love everything about these displays, not least the sound they make while in operation. I would LOVE to build something using these little rascals. My mind is buzzing with ideas. How about you? Could you be tempted to create something with these little scamps? If so, what?