DuSI
Although DuSI can be installed permanently if you wish, by copying DuSI.jsx to an After Effects ScriptUI Panel for example, if you just need to run it once, you can just use the “File/Scripts/Run Script” menu entry.
DuSI
Related
Free: Duik Ángela: Camera Tools (en/fr)
In this tutorial, you’ll learn everything about the multipurpose Connector.
Beta Tools
This is still a Beta version, which means there’s still some development remaining, but it is already considered "usable". i.e. you can already use it without breaking the sun, there may still be some bugs. You may use it in production at your own risk.
Ramses
Ramses, the Rx Asset Management System, is a complete framework to help you, your team, your studio, plan and track the production of your films and automate your workflow.
Duik Ángela
The brand new version of the comprehensive rigging and animation tool set for After Effects.