A Finite State Machine Editor, written on QT.
It allows to draw Finite State Machine with easy GUI and store it in XML file.
There are Finite State Machine Compilers to translate this description to source code (technique like QT's UIC uses).
Log any javascript or php variables and it's back stack into file like php function debug_backtrace done. View the variables value and it's back stack info in web browser, and browser will synchronize with the log file using ajax.
AG101 is a java-based visual XSL editor/debugger built on the Pollo XML editor (pollo.sourceforge.net). It has extensions to a regular expression library. It also has the ability to pipe XSL transforms one to another and store and reuse those pipes.