UnityEditor namespace:
- ./Editor
- ./Plugins/Editor
- ./Standard Assets/Editor
- ./Pro Standard Assets/Editor
(can we have an "Editor" folder elsewhere? probably not)
Native plugins:
- ./Plugins
- ./Plugins/x86
- ./Plugins/x86_64
- ./Plugins/Android
- ./Plugins/iOS
First pass:
- ./Standard Assets
- ./Standard Assets (mobile)
- ./Plugins
- ./Pro Standard Assets
First pass, part two:
- ./Standard Assets/Editor
- ./Pro Standard Assets/Editor
- ./Plugins/Editor
Main pass:
- All other scripts not in "Editor"
Final pass:
- ./Editor
Gizmos (textures usable by Gizmos.DrawIcon)
WebPlayerTemplates (no scripts will compile, see manual)
- http://wiki.unity3d.com/index.php/Special_Folder_Names_in_your_Assets_Folder
- Various pages of the Unity manual