Nash is a new class of program developers IDE (Intergrated Development Environment)
Designed to be ultimately language independant (aren't they all) Nash will work with your favourite language and compiler with scripted addins.
Nash is "not another syntax highlighter" because it is aimed at understanding your code, it does this by presenting your code in an easy to understand graphical form.
Unlike many IDE's which go to great pains to represent your classes and objects in an easy to see form, Nash tries to present your actual code in an easy to see form, so that tracing throught the code is easy and intuative.
Ultimately this will be a great benefit to those of us who are told "This is the previous programmers code... Fix it"
By making it easy to see the structure and flow of the actual program, and not just its classes, deciphering what that old bit of forgotten code does should be easier.
Nash itself does the organising and display work, by delegating the deciphering(parsing) job to a scripted environment it allows third party developers to create modules for working with their favourite language and compilers/interpreters.
These plugin modules provide the funtionality that interfaces between the various modules in a uniform way.