Or, the art of taking pics of monochrome devices in color
We'll take this picture:
In your editing software, you should be able to decompose it in its different channels:
GIMP: Colors > Components > Decompose...
Take either some old non-Color Game Boy, a monochrome TI-83, or a e-ink device and find a way to write a ROM, a program, or import each of these three pics on that device.