I promote the professional NoteCase Pro outliner by Miroslav Rajcic (Virtual Sky) and develop Plugins for it extending its feature range and giving it even more professional use.
Everyone with decent programming skills can extend NoteCase Pro with new features quite easily by writing Plugins. All you need to do is learn the Lua scripting language. No additional tools are required. Development is done within NoteCase Pro. For anyone interested in developing own Plugins, I recommend usage of my "Plugin Developer Tools" Plugin, which makes development of Plugins very easy.
All NoteCase Pro and NoteCase Pro Plugin related contents of this website have been moved to a dedicated website:
http://www.NotecaseproPlugins.com
The official NoteCase Pro website is:
http://www.notecasepro.com