UML
ArgoUML - free UML modeller ArgoUML is a free modelling tool that helps you do your design using UML 1.3. Requires only Java VM runtime. Forward/reverse engineering, export GIF/PS/EPS/PGML/SVG, supports XMI (Oct 2003)
gModeler - free online UML diagramming tool gModeler is a free online UML diagramming and documentation tool, targetted at developers working with ECMA 262 languages such as FlashMX's Actionscript, and Javascript. In addition to it's diagramming capabilities, (Oct 2003)
My Little UML Page Michael Godrey's My Little UML Page lists UML editing resources for open source, commercial, and dead products. Informative. (Oct 2003)
Umbrello UML Modeller Umbrello UML Modeller is a free Unified Modelling Language diagram program for KDE (Linux). Supports all diagrams, icons, associations, etc. (Oct 2003)
UMLet - lightweight free Java tool for UML diagram UMLet is an open-source lightweight Java tool for rapidly drawing UML diagrams, UMLet lets you draw diagram sketches fast, teach UML using a simple user interface, and export diagrams to SVG, JPG and PDF forma (Oct 2003)
Violet - lightweight free UML editor Violet is a UML editor with these benefits: easy to learn, draws class, sequence, and state diagrams, free GPL, cross-platform. Intended for students, teachers, and authors who need simply UML diagrams quickly. (Oct 2003)
Visual Paradigm - UML CASE tools Visual Paradigm for the Unified VP-UML supports the latest standards of Java and UML notations and provides the industry's full round-trip code generation and code reverse engineering support for Java. Free edition for educational institutions (Aug 2002)
Books about UMLA complete list of books on UML available through Amazon.COM