I'm sure many people here watch Primitive Technology, but some don't and his latest video is noteworthy for being about the construction of a machine that works without human intervention. I don't know how far back these machines go in reality (and I doubt if anyone does - how could it be determined?), but he built it using only technology that we know predates humans by hundreds of thousands of years. Homo Erectus could have built these over half a million years ago.