Surplus, of course, has been the best place to get stuff for repairs, ... but further, to leap ahead for invent.
University research labs on small budgets, high school students just getting started, and small companies all able to take advantage
of Obso, over-run, or cancelled project debris. No matter where, from Boston/MIT, Harvard; Eli Hefferon & sons, or the many in New Hampshire, and many more down the coast to Florida, due to the Cape; Dayton forever(lets hope), the many in the midwestern states and the huge surplus warehouses in silicon valley & up the coast to Boeing surplus sales, and beyond (Hello Walter !).
One could spend a lifetime wandering through them and most assured able to find treasures of yesteryear, "... ah ha, that's how they did it".
fortunes were spent on the design, engineering and construction of a part, let alone systems, materials and processes that wandered off to surplus floors, and then to the high temperature kilns or landfills of history. We do not even know what we have lost, and the old timers who knew that something of value still remained.
It is a hard day indeed when that source dries up...
While barely detailed in "The Hackers", ...at least the surplus "concept" was mentioned.
There are details of technological history in the remnants that might never be comprehended.
Curiously, Surplus junk yards are often a short-stop in movies such as the various Star Trek's( even in Discovery, etc.), Star Wars, & so on...
May they ever be there for us & those that follow, for the future.