Most recently I've been using a simply sticky note application to approximate what Workflowy does, but of course, Workflowy does it much better and more robustly. It's that simple, though. It's just about lists, but the combination of the potential depth and the simplicity of the interface is what makes it so useful. What I mean is, you don't have to look at it and think, "Now what did I call that list I was looking for?". Your lists of lists is right there. Genius!
It needs a few more touches, of course, and they'll probably appear shortly if Workflowy is successful. They probably won't need my wishlist, but I'm making one anyway:
- Widgets. You have to have widgets for home pages, etc. so that your organization-impaired users don't actually have to navigate to the site to see their most important to-do thingies.
- Collaboration. I never, ever use collaboration tools, but this cries out for sharing. With a notation as to who last edited a shared list in case we forget to write it down. I can totally see this being useful at work. Totally.
- Sharing. I guess. I never do this either, but there must be some way that you can use this with Facebook. I assume that you can use anything in the world with Facebook. I kind of hate Facebook, but that is really a whole other post.