How to rotate Pivot point - User Feedback - Developer Forum
Blender Market - Pivot Transform helps you change the position of the pivot point as needed. You can align it to the normals of the desired polygon, rotate and move it, or
Best Blender Addons and Plugins (tested & updated for 2021) - CG Cookie
Free Pivot Painter addon for interactive foliage in the Unreal Engine - BlenderNation
Poor pivot workflow impedes Blender's modelling proficiency - User Feedback - Developer Forum
BS Modify Pivot Add-on - BlenderNation
The new 2.81 Feature -> Option: Affect Only Origins - User Feedback - Developer Forum
GitHub - gandalf3/snap-cursor-to-view-pivot: Blender addon which snaps the 3D cursor to the view pivot point
Great Blender Addon for Concept Art | Simply Concept - InspirationTuts