They built spy satellites during the Cold War.
(Click to enlarge this formerly top-secret document.)
When I was a kid, either a relative or a friend of my family (even my mom can't remember) worked at the Perkin Elmer company in Danbury, Connecticut. As a kid, I didn't know or care very much about what adults did for their jobs, but in this case, if anyone had squealed, I would have been fascinated:
For more than a decade they toiled in the strange, boxy-looking building on the hill above the municipal airport, the building with no windows (except in the cafeteria), the building filled with secrets.
They wore protective white jumpsuits, and had to walk through air-shower chambers before entering the sanitized "cleanroom" where the equipment was stored.
They spoke in code.
Few knew the true identity of "the customer" they met in a smoke-filled, wood-paneled conference room where the phone lines were scrambled. When they traveled, they sometimes used false names.
At one point in the 1970s there were more than 1,000 people in the Danbury area working on The Secret. And though they worked long hours under intense deadlines, sometimes missing family holidays and anniversaries, they could tell no one — not even their wives and children — what they did.