orgmode does this insanely well and looks like what workflowy does but less flashy and not web-based. You can narrow to a subtree (see C-x n s) and then un-narrow (see C-x n w). In addition, you can track todos, record data in tables, export to html, PDF, or even a Beamer presentation.
Anyway, it's pretty darn amazing. I've hunted around a lot for various notes/todos solutions, probably like yourself -- OneNote, EverNote, Google Notebook, TiddlyWiki, Monkey-Pirate-GTD-TiddlyWiki, TaskPaper (also pretty much what Workflowy looks like), Task Coach, iGTD...
Nothing has touched orgmode :)
I wrote a little bit about it on my blog HERE.
Emacs has a steep learning curve, but it can't be any more time intensive than rolling your own code!
Yeah, I've tried org-mode, but the problem isn't that its Emacs-based (I use Emacs to write code), but it's that it isn't web-based. I wanted my notes to be accessible not only from both OSes I dual boot, but from pretty much any computer I might ever be at. I could make the file accessible I guess by putting it in a Dropbox public folder, but then there's still the issue of "what if the computer I'm on doesn't have Emacs".
Also the time-intensitivity thing of rolling my own code isn't a major drawback, as I'm trying to find a programming job at the moment and I needed something to add to my portfolio. :D
The is the second 'What are you working on?' thread. The last one is here. So here's the question:
What are you working on?
Here are some guidelines