For my physical negative filing sysytem I am banal, but it works.
Films get developed.
After hung and dried the films are cut and put into filer sleeves. 35mm, 120 (in 3 verticals for the TLR or 4 3's horizontal for folders etc.) or 4x5.
If it is b&w the type of developer, dilution, time and temp gets written on the top of the filer page with a fine tipped sharpie marker. Sometimes films get stockpiled waiting for enough to make a batch worth mixing up some e-6 or c-41 to use it to its full capacity. E-6 and c-41 might get the replenishement sequence noted on the filer page if I am in the mood to try to see if the image degrades excessively by re-usung the chemistry too much.
They get put into a binder called 'contact printing backlog', generally in the order in which they are shot. With multiple cameras on the go this is not always feasible.
They get assigned a year and month number and stuck into the binder, regardless of type: B&W sits beside e-6 and c-41.
Then after the backlogs are all cleared, the month sequence number is added. So the fourth film in about chronological order processed this month becomes 2012-11-4. The individual frame numbers finish the index, reference or , if the film is not not frame numbered (arista, some cinema stocks) they become referenced as things like row 3 frame 2. 4x5 go four to a filer pages and become A, B C and D.
The next time I am printing that process, I pull all of the backlogged films of that type, and make contact sheets. E-6 gets contacted as negatives with some old no longer fully black monochrome RA-4 paper when I have the roller processor revved up to print from colour negs.
The contact sheet gets the film negative page reference written on it, and the back of the page gets notes of anything unique I wish to recall about where I was. it also gets any model releases for images on that paged taped to it. The now contacted pages go back into the contact sheet backlog binder, and stay there until most of the other filer pages of their era are finished up. Then every few months or longer, they get transferred out to a year binder.
The year binder has a clear plastic front and rear slip in cover that allows a a hand written index to be compiled and slid in. This index could be computerized and more searchable, but so far I have not gone that path. The index notes the number of the film, the film format ( 35, 120, 4x5, or other ) then the process (b&w, e-6, c-41, or other), then a general description of what is on that film/page.
The filer pages go in the three ring binder behind the contact sheet. Some filers have a sleeve for the contact, but usually they are too pricey, and I just punch the contahc sheet carefully so an 8x10 fits to the holes more commonly meant for 8.5x11.
The index sheet frequently extends to half way onto the back of the binder. I use 1.5" thick D ring binders. I have about 6' of shelf space of them now. For the last few years I have needed a first half and second half of the year binders for any given year.
The system is imperfect, but usually I can recall about when I took an image, and find it with the negative in my hands in less than 10 minutes.
Most of the contact printing is done when I am tired and just housecleaning in the darkroom.
Printing better enalrgement prints usually waits until I am more rested, which typically means more inspired.