My father used to work at a US Naval Yard as a mechanic (I won't mention which one!). When he passed, I inherited his fasteners, which I named the Fabulous Fastener Collection. OK...you've read about the crazy prices the government spends, like $100 hammers and such? Well, this is what they were. You don't find these at your local Ace or Home Depot. And stainless out the wazoo (think Navy aircraft). Took me months of spare time to sort them all. Was kind of cool because it was my dad's stuff. Used many of those plastic drawer organizers. If they wouldn't fit into one drawer, I'd just keep filling the next successive drawers.
My wife had a friend who was a mechanic and tinkerer. He would always brag about what he was building and fixing, would talk non-stop. I finally brought him into the shop to show him the rows of many organizers filled with fasteners of all kinds. It was the only time I knew him to stop talking--he halted in mid-sentence and just stared. Priceless.
Great stuff, has pulled me out of running to the store many times. One problem, though, in today's world--it's all SAE. No metric.