Businessweek has this little slideshow of a LEGO factory. Neat. Apparently the system is so precise, only 18 in a million LEGO bricks are defective. Which sounds about right; I’ve never found an irregular LEGO, and I’ve handled thousands.
Still, a LEGO-making factory is just not as impressive as a factory made from LEGO. Someone with apparently infinite patience built a car factory out of Mindstorms LEGOs and posted it to YouTube. There’s no narration, and it’s kind of hard to see what’s happening, so you just have to have faith until the end; but the machinery itself is hypnotic.