I find that when you have lots of file folders you can easily forget what's
in them even if you can see them all at a glance. A file index is
invaluable to me, especially if it is on computer and can be
keyword-searched. It also prevents duplicate or similar files being
created.

I also use a PIM called Corkboard which lives on my computer desktop and
enables me to "paste" sticky notes, "To-Do" lists, a calendar, and a phone
with speed dialing on my virtual corkboard that also serves as a
screensaver. Kinda attractive, too, and if you're into this sort of thing
you can send harmless pranks across a network. Depends on how much time you
have on your hands, I guess.

Then there's always the file it, mail it, delegate it, or chuck it rule.

Nancy Kramer
Dragged kicking and screaming into organization