A free bare bones OSX outliner called ‘Deep Notes’ shows a lot of potential and I’m enjoying using it. It’d be nice to be able have an alias of it in the menu bar so I could have it pop to the front without having to remove Firefox (or whatever else might be using the desktop) and it took me a few minutes to figure out the ‘New Item Below’ shortcut (command / return ). Other than that, pretty cool. Highly recommended!
http://amarsagoo.info/deepnotes/