[broken link! FIXME] Having worked as a truck mechanic, and having grown up in the household I did, I have a strong interest in (and fascination for) engines, although I never developed the level of passion for vehicle mechanicking that seems to have been my birthright (by which I mean my father, grandfather and great-grandfather were/are all passionate mechanic hobbyists).
Some guy in Spain makes miniature engines that actually run. Here's a video of him putting together and testing a V12 engine. I think it's really interesting.
Slightly related to the above (in the aspect of "hand-made" industrial devices), I also ran across a story about a guy who tried to make a toaster "from scratch" – I mean really from scratch. I think it was meant as a sort of performance art. It's intriguing.
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