Structorizer is a little tool which you can use to create Nassi-Schneiderman Diagrams (NSD). Stuctorizer is written in Java and free for any use.
The code has been moved to Github:
https://github.com/fesch/Structorizer.Desktop
Unimozer intends to be a universal modelizer for Java™. It allows the user to draw UML diagrams and generates the relative Java™ code automatically and vice-versa.