Although I've played with EagleCAD before, this is my first serious attempt to master it. After many days, it no longer feels like I'm holding a paintbrush with boxing gloves. But I'm far from having a direct connection between my brain and the canvas. If you have tips for me, I'm all ears.

The cube is connected to the Arduino via 16 I/O pins. Although I would like to design ONE multi layer PCB, the free version of EagleCAD only allows for two copper layers (top and bottom). Furthermore, because everything is so small, I only have room for one via or two traces between the LED pillar leads.

I was able to put the first eight wires on one PCB:

The next four wires on a second PCB:

And finally the last four wires are on a third PCB: