Basically the concept was instead of engineers having an assigned office or desk, the office would have a large field of unassigned desks and generic equipment. Every day you would come in, reserve a desk, take any belongings from a locker, and set up shop. At the end of the day, you would tear down, lock up, and leave.
It is beautifully efficient from a top-down perspective, but it turns out employees like the consistency of a known work location each day. Its also nice to be able to put up a picture of family, from what I gather. I suspect the cost of personnel replacement dwarfs the saving of n% reduction in desk need.