Open Source / Non-Proprietary
according to its developer, is a Windows-based UML tool with scripting for forward engineering. Scripts are provided for generating Delphi, C++Builder, Java and VB code. Available in Professional and Standard versions, plus a free read-only viewer.
EctoSet Standard is a tool for UML software modeling. Many aspects of EctoSet can be customized - diagram colors, component tab switching, custom data types, visibility specifiers. Diagram print-preview permits you to selectively copy portions of diagrams to the clipboard making it easy to paste your diagrams into documents. An entire project is stored in a single project file using XML. Third party XML tools can be used to examine the content of your project. You can even drag and drop a EctoSet project file onto Internet Explorer and examine the XML structure. With scripting you can generate code from your classes - right from within EctoSet. The scripting language is a fully featured language that provides read-only access to EctoSet data structures.
Not sure where the official home page is at this point.