Bert send me this cool animated GIF of a machine making chains. Lovely, simple, very effective.
I am always amazed at how they can just press metal into shape. Apple today showed a video of the making of the upcoming new Mac Pro. If you like technology, the keynote presentation is worth it just for that. It starts with a big circular chunk of aluminium being put into a shaped hole. Then a shaped thing comes from above, and in a second simply presses the chunk into the cylinder it needs to be. Holy moly, what force!
It's a short video, starting at about 37 minutes into the keynote.
... And that's just the relatively soft aluminium, they can also do it with steel:
The force applied is 800 tons, about two fully loaded jumbo jets!