The equivalent of software engineering in Ancient Greece.
I stumbled upon Jason Allemann's amazing kinetic Sisyphus sculpture a while ago, and finally got around to buying the bits for a motorized one just before Christmas. It's very easy now: the rebrickable page will autofill your Bricklink wishlist, and a button on that site will go and find a small set of suppliers. I did business with Alpine Bricks in Austria and 3 BRICKS in Slovenia; amazingly I received only ony incorrect piece out of over 1200. I'm glad I held off as the redesign of last year reduced the cost significantly.
I spent perhaps ten hours building it over three lengthy sessions. The instructions are very straightforward for building techniques this clever. It felt like most of the time went into the decorative murals. It's large, works as advertised, and the mechanism didn't require any tweaks. I can't imagine pulling it apart.