I’m dropping science, son!
A group out of Woods Hole, MA recently ran experiments on the giant axons of the Longfin Inshore Squid (loligo pealei) specifically relating to the the fast color-changing nature of the squid’s skin (The reasons that make them turn colors several times per second on command). Squids can quickly control pigmented cells called chromatophores to reflect light. The Longfin Inshore has 3 different chromatophore colors: Brown, Red, and Yellow. Each chromatophore has tiny muscles along the circumference of the cell that can contract to reveal the pigment underneath. This gives them an illusion similar to a strobe light or bioluminescence.
In so many words they wired an to an iPod nano to one of these suckers as a stimulator for the color change. The results were both interesting and beautiful (AKA fucking sweet) and can be seen in the video shot through an 8x microscope zoomed in on the dorsal side of the fin.