A nod to the platform on which these clocks are being made, here I'm taking advantage of the way that color is represented in a digital context.
Each 'digit' of the time (though in this case, it's mostly irrelevant whether it's analog or digital) is fed into one of the color parameters for the clock's face.
Color is calculated in 3 bytes, 1 per color. Each measure (hours|minutes|seconds) are mapped from their own range (0-24 for hours, 0-60 for the others) to a scale from 0 to 255 (the maximum value for any component of a color on the web
The 'hours' control the red, the 'minutes' the green, and the 'seconds' the blue. The result is a unique color for every time of day, that moves through the whole color space in a jagged, seemingly random, but completely organized way.