Clockwork wristwatches? The movements are pretty ingenious, though sadly there's only a couple standard ones that get riffed on. I recently found the "Wristwat

Clockwork wristwatches? The movements are pretty ingenious, though sadly there's only a couple standard ones that get riffed on. I recently found the "Wristwatch revival" channel on YT where a hobbyist restores vintage watches while being very informative.