A list of UnifiedModelingLanguage (UML) software (or UML tools), in alphabetic order. Every tool is listed by it's name, followed by a short description and an external link to the homepage (if available).
Please put longer descriptions (more than a few lines) of a tool to it's own page. (See AddingNewPages, OneMinuteWiki)
CadifraUmlEditor -- Commercial UML diagram editor for Windows 2000 and XP. Fast and lightweight. Unlimited undo/redo. Can embed into Microsoft Word (and others). No code generation. -- http://www.cadifra.com
Dia -- Open source, GPL'd (IIRC) graph editor targeting Visio-like functionality. --DanMoniz