I designed and constructed a coat with the constellations of the summer sky. It's dark blue cotton, with a sheer applique representing the Milky Way.
On the front it has Cygus, Saggita, Aquila, Corona Borealis, and Lyra:
On the back it has Draco, Ursa Minor, and Ursa Major:
Each star is an Adafruit NeoPixel. The stars are chained together and controlled by an Adafruit FLORA microcontroller board and powered with a small battery pack in one pocket.
The FLORA runs a bit of code that smoothly fades the individual constellations in and out.