The Outliner of Giants
The 16.0 version of The Outliner of Giants for Mac is available as a free download on our website. The actual developer of this free Mac application is theoutlinerofgiants.com. The Outliner of Giants for Mac is included in Internet & Network Tools.
From the developer:
The Outliner of Giants is a feature rich Outline Processor designed to support the creation and management of large corpuses of information, such as those generated by students, researchers, writers and project managers. It's secure, using Google's user accounts system and an encrypted internet connection.
You may want to check out more Mac applications, such as Red Giant Link, Cloud Outliner or Cloud Outliner Lite, which might be related to The Outliner of Giants.