Text Tree
- Text tree is a text editor / outliner used to help make structured, understandable documents easily and clearly.
- http://www.babykatiemedia.com/texttree/index.php

StoryRight
- A web application that helps a writer plan their story from initial concept to a full story plan, outline, complete with character dossiers.
- http://www.storyright.com/

Idea Cruncher
- A simple program for Microsoft Windows that helps you organize ideas. Good for writing, brainstorming, to-do lists, outlines and other planning tasks.
- http://www.ideacruncher.com

MacFlow/WinFlow
- Extremely adaptable and intuitive flowcharting program. Lets you import an existing outline from text directly into diagram mode. Allows for "nested" diagrams, i.e., placing shapes within shapes. Free trial download available.
- http://mstay.com/fl40_ab1.html

Acta
- An original outlining software written in 1993 for Macintosh computers, now available for free download (Mac only). The site provides interesting background on the program and its uses.
- http://www.a-sharp.com/acta/acta.html