I've meant to finish this years ago, but I never got around to figuring out the proper cubic bezier timing funtion that most closely matches a cosine.
The idea stemmed from two different illusions, which I have since lost the links to.
The first was a series of dots that oscillated on straight lines to produce what appears to be a ring rotating around a larger percieved circle.
The second was a series of cirlces rotating to produce what appears to be waves.
Having seen both illusions I decided to throw them together—which I started to do a couple years ago—and then promptly forgot about it.