Below is a video that shows how to develop black & white 35mm film using instant coffee and vitamin C powder. It’s… kind of weird, but looks like it works. I set up a real darkroom a few years ago when I was still at my parents’ so I probably won’t be trying this any time soon, but watching it took me right back to all those days at college when I barely saw daylight.
I’d spend 8 or 9 hours a day hidden away in the photography dept with only the radio and the occassional art student for company. (When you see how many times the solution needs agitating you’ll understand why a radio is the only thing that stops a lot of old-school film photographers going slowly insane while developing the films.)