A number of people have linked to Michael Fitzgerald's recent editorial on tagging in CIO Magazine editorial, The Name Game. He focuses primarily on the tools people have been using on the web and how companies are beginning to pick up on the tagging phenomenon.
While the folksonomy (social) aspect of tagging (del.icio.us and flickr) is fun, I want to start using tags in my personal space as well. And I want a single system that lets me tag anything, not the mishmash of tools that have their own idiosyncrasies. Outlook lets me apply multiple "categories" to items, but then most search tools don't recognize those categories. Outlook's search treats this as a unique field, making it difficult to search against. The Windows browser actually has the option to add keywords to files, but its rather buried under file properties -> summary. It's never been clear if the search tools see these properties. I've just learned that Adobe Photoshop album lets you tag and find photos, but again this is limited to just photos. If Vista ever comes out, it is supposed to have tagging built into the file system.
I want a tool that will let me apply and browse tags over email, files, pictures, website, tasks, appointments, contacts -- anything on my machine. Oh, and if I can apply my own hierarchy to some of the tags, that would be super. Sure, I want to be able to limit to specific types, but I want to do that all from one place. The desktop search tools are great at finding things based on their title and their content (for standard file types). But I'm thinking that tags would give me another way to find my stuff. Five years ago, I purchased PersonalBrain because it offered some things along these lines with the notable exception of being partially isolated from Outlook. I still use it, but not as heavily as I did initially.