Open Source / Non-Proprietary
Based on the latest Mono, GTK+ and ExpertCoder. Can reverse engineer executables and .NET assemblies.
"MonoUML is a CASE Tool designed to allow developers faster computer-systems design. MonoUML is not only a diagramming tool but rather a complete CASE tool based on standards defined by Object Managment Group. Our goal is to implement CASE tool for doing Software Engineering tasks better, faster and easier. "