UML Sculptor (unofficial)
UML Sculptor is a lightweight UML modeling tool for class diagrams.
It is not a complete UML solution, it doesn’t do round-trip engineering and it consists of only a single executable file. But because of that, it’s exceptionally quick, easy to use and provides an excellent workflow.
For example, to add a method to a class, instead of selecting a class, then opening a tool window, picking public/private from a combo box, entering a name, clicking on ‘add parameter’, yadda yadda — in UML sculptor, you just click right below the methods compartiment of your class and enter + myMethod(arg : int). No tool windows, no dialogs. It feels just like drawing the diagram on paper!
That makes it ideal for quick sketching and planning, where I very much prefer it to bulky, full-featured UML designers.
This is a modified release of the original UML Sculptor, statically linked against the Visual C++ runtime so it runs without installation. I also added the ability to directly export UML diagrams to SVG (XML-based vector graphics format supported by all modern browsers except for Internet Explorer.)
Below is an example of the added SVG export, showing the example class diagram from the screenshot before. It’s not a bitmap – try zooming in and out or doing a print preview!