The project was cheap to make, simple to design, and helped me kill some time while waiting for a 3D print to finish. The only real trick to this was making the blue, cross-bar a bit longer (1/8"ish) than the space where it fits. I did this to make up for any extra space gained during bending, and to ensure that the white tray would squeeze the bar tight enough to hold it all together.
I found the vector version of Peaches on nagutron's Laser-cut Laptop Screen Protector project and, with a bit of tweaking, managed to get it etched into the side of the caddy. I painted the etching, let it dry, and then wiped away the excess paint with diluted rubbing alcohol, which is the same technique I use for inking my (nerd alert) GameScience dice. The design isn't quite a natural 20; if I had it to do over again I would have made it fit two rows of spools, but I'm still very happy with the execution.