So for this years present to my nephew, we made this:
Before gifting, we added the ability to show letters (and so had it randomly choose quotes from Star Wars and Ninja Turtles), and some more pretty displays (twinkle, centipede).
The tubes are pvc, the box mdf. My dad and my son were involved in the assembly....gads the soldering was a pain. Two 7219s, RBBB. I am making another one with RGB leds for us to put in the pinball room and will share code at that time.