Vetinari's Clock (2011)

In Cambridge we've got a clock called the Chronophage which is intended to be a sinister "eater of time" - the designer has done a good job of making it feel uncomfortable to look at. There's some detail here: https://www.corpus.cam.ac.uk/articles/secrets-corpus-clock

My memories of what I've heard over time:

* The grasshopper escapement actually is the demonic insect that sits on the top, "walking" around the serrated ring.

* Although it's backlit electronically it's actually a fully mechanical design - including all of the weird things it does.

* The Chronophage itself blinks its eyes unnervingly.

* It sometimes pauses or ticks slightly backwards, then runs faster to catch up again.

* On certain special dates it does extra weird stuff.

* The "chime" is a metal chain dropping into a box.

There were three made in the series, this was the first one. I've always found it slightly unappealing aesthetically but also compelling - there's no arguing with the fact that there's always a crowd of fascinated observers looking at it.

How do you build a completely analog "random" system? Building a regular one is easy, building one that might seem random because of how many regular ones are tied together ... but true sources of entropy?

I would imagine that analogue randomness is easier than doing it in a deterministic digital system. Surely there are all sorts of creative methods. Dice or coins in a box? A ball falling through a galton board? Sampling a double-pendulum? Floating particles in a heated liquid?