Dennis Kennedy makes some interesting observations as he thinks out loud in KM Resources - Search and Taxonomies White Paper, Blog23 and Twyla Tharp. Can't wait to see what comes of the presentation on KM that he is preparing. One idea is about how I personally work with information
Both my personal interests and my categories do change (I'm about to dump my latest effort at creating a useful subfolder system and try another, much looser, one). Categories and documents make the most sense within the applicable context. In other words, I regularly find that I do not know what the "right" category is (or whether an "info object" should be in more than one category) until I am in a place where I want to use it.
I find this same problem myself, an I am sure many others see it too. Building any complexity into my filing system will work for me until I learn something new about the area in which I am filing. And what happens when one "branch" of stuff crosses with another "branch." Do I file in drawer 1 or drawer 2? Even worse, will I remember which draw / folder / etc. I dropped it into in three weeks when I want to retrieve it. But if I leave the system simple - maybe one folder for everything - there are too many things in there to make it easy to find what I want. Even worse, as Dennis mentions, I frequently realize that I want some reference material when I am doing something quite different than what I was doing when I found and filed it originally. As a result, my brain is working in a different mode and can't always remember how and why I filed that way.
In the past, I have been very happy with PersonalBrain, because it lets me file things in multiple places, and it makes it "easy" to add items to categories over time. It still requires that I remember where I filed it - either its parent folders or its name. These days, I am using it much less - I don't do as much document and article filing now that I am working on my own. Much of my "interesting stuff" ends up here, on my blog. I still need to find it from time to time, and I have relied on search tools much more than the categories I've set up.
Dennis echoes this in the topics in his article. Effective tools for me will have to let me find my information in a variety of ways, and they will have to be flexible to deal with my fickle sensibilities. Oh, and they have to be easy to use, if I am going to stick with them.