GTD = OmniFocus + OmniOutliner + DEVONThink + ...
My GTD workflow is for the most part a connected system of OmniOutliner documents managed by DEVONThink with the actual task-work managed in OmniFocus. Other than that, I use a metal inbox next to my desk as a primary collection bucket and a raised file-rack for project support and tickler files. I also have a whiteboard next to my bed for midnight thought streams, and I use my iPhone for on-the-go collection.
The first thing I should note is why I use DEVONThink over other applications that accomplish the same purpose. The main reason is that DEVONThink is designed the way I think. Everything is laid out in a hierarchy with documents that are inter-related but not of the same category. DEVONThink handles a lot of the extra relations between documents on its own and displays them if I ask to see them. Otherwise, it acts like a customizable Finder with built-in editing tools. That’s an oversimplification, but the power is really quite beautiful.
I first realized how much mileage I could get out of combining DEVONThink with my OmniGroup documents when I realized exactly how little I kept project support folders. So, I set up a Productivity database. I started by copying in most of the lists from the GTD book to text files. That means easy look-up for trigger-lists and weekly-review guidelines. As my current set up stands, those exist in a top-level folder called Lists. I then have another top-level folder called Projects which holds four sub-folders: Current, Incubation, Archived, and Someday/Maybe. Each sub-folder holds its own project list which is a OmniOutliner document. These lists are then replicated to the top-level Lists folder for quick-access. The sub-folders also have their own sub-folders which are project support for individual projects.
What makes this setup so great is that during my weekly review, I have everything I need at my finger-tips. Plus, shifting data is simple. Since my project lists are in OmniOutliner, I can have all 4 documents open at once and easily redistribute projects as the review deems necessary. Also, since I have these are digital files, I just drag-and-drop project support from one category to another. Project becomes active? Move from Incubation to Current. Bandwith dead? Shift+click and drag a bunch of projects from Current to Incubation.
What is marvelous as well is that I don’t have to toss old project support to make space. So, when I need information from that project I finished a few weeks ago, I just go to DEVONThink’s global search and start typing. Or, I can see when support for one project may be relevant to support in another project using what I call DEVONThink’s “mad hatter” function. (It’s actually called “See Also & Classify”, but it looks like an upside down top-hat.)