Large Hadron Collider – The prototype is the product
About the largest and most expensive prototype ever.

Image taken from somewhere on the CERN website. Recorded with the VELO detector.
But above all, it is the largest and most expensive prototype ever built. Something like the LHC will obviously not go into mass production. The first run is the first test of the product –or system– as a whole. If there’s something running out of protocol, the engineers gotta manually fix it while in service (not with Gaffer tape, though). There are a lot of “live” measuring instruments and analysis software tools connected to it (apparently, numerous scientists around the world are locally disassembling and interpreting the data). And the world is its focus group.
Fascinating.
As always, there’s some nice and insightful interactive visualisation coverage around the Large Hadron Collider project over at the New York Times.