WordPress has a feature know as a Tag Cloud. As I get time I will be going over all past posts and adding a tag to each post. I started it a week ago and didn’t like the way I had done it, so I am going to try it again.
This will not replace the category field, but will hopefully augment it. Time will tell. When it is finished, the size of the word in the Tag Cloud will reflect the number of posts classified under that tag. The Tag Cloud will be found at the bottom of the right sidebar.