By now everyone knows what a wiki is, right? One of the best features of wikis is the ability to easily discover links between different bits of information. I have used various “wikipads” like Tomboy and ZuluPad, for example, which automatically highlight links to other notes.
This is especially valuable in complex cases, where you may be dealing with a variety of issues, strategies, causes of action, defenses, and so on. Give a page to each and watch the connections emerge, potentially leading to new strategies, etc.
TiddlyWiki is an interesting wiki option because it is only one file. You can host it on a website, your own computer, or your office file server.
Because it is only one file, you can easily use a separate TiddlyWiki wiki for every file, and everyone in the office can use it to build a useful database on the file. I would just stick it in my blank file folder template, and every member of the staff would know to automatically use the wiki for leaving notes on the file.