I don't have any junk drawers in my toolboxes. But I do have some junk bins on my poly-bin rack. Weird fittings and fasteners that don't really fit in anywhere, but I don't want to throw them out. Same with a bucket of large electrical fittings/connectors I keep under my workbench. I'll probably never need them, but they can be pretty expensive if I do ever need them, so in the cobwebs they wait.
I used to be the guy who kept "junk" (bolts, washers, wire clippings, etc) strewn all over my toolboxes and trays, but not anymore. I've become obsessively organized, and it helps my productivity immensely not scooting piles of random junk around looking for tools, or scooting tools around looking for random junk.