Opensource Applications

UMLet is an open-source UML tool with a simple user interface: draw UML diagrams fast, export diagrams to eps, pdf, jpg, svg, and clipboard, share diagrams using Eclipse, and create new, custom UML elements.
UMLet runs stand-alone or as Eclipse plug-in on Windows, OS X and Linux.

Frame UML is a free UML tool that supports UML 2.xx. It can run on Windows(2000/XP/Vista) and generate source code /CHM from model, or parse source code into model by JavaScript. It supports 12 kinds of diagram except object diagram. It is very nice,simple, and easy to use.

Umbrello UML Modeler is a UML diagram tool that can support you in the software development process. Especially during the analysis and design phases of this process, Umbrello UML Modeler will help you to get a high quality product. UML can also be used to document your software designs to help you and your fellow developers.

UML2 Tools is a set of GMF-based editors for viewing and editing UML models; it is focused on (eventual) automatic generation of editors for all UML diagram types.
The diagrams that will be initially supported (as part of the first release) include class, component, state machine, and activity diagrams.

BOUML is a free UML 2 tool box that allows you to specify and generate code in C++, Java, Idl, Php and Python. It runs under Unix/Linux/Solaris, MacOS X(Power PC and Intel) and Windows. It is also very fast and doesn?t require much memory to manage several thousands of classes.