Has anyone played with the captioned? I'm finding that it's a fantastic tool for managing GTD with. The nicest function is that you can markup your text, anywhere, like this:

todo.home: clean dishes

and the software will extract all of these tags into a special, real-time list. This means you can maintain all of your projects as separate Wiki pages, but always have the various next-actions compiled into a single list. Great stuff!

http://www.jhorman.org/wikidPad/

Not freeware, but modestly priced ($12)
-John