Easy Video Editor - graphical interface to non-linear video editor
...Write your own transforms in javascript and run them in gorp - complete with persistence to file, and parameter editing/checking through the GUI.
Your work is saved as a text-based script - furure tools will allow direct scripting.
AVISynth UI is a user interface for the script based video editor AVISynth. Written in Visual Basic, It enables you to edit videos using AVISynth with the comfort and ease of use of having a user interface.