Easily create beautiful UML Diagrams from simple textual description. There are also numerous kind of available diagrams. It's also possible to export images in PNG, LaTeX, EPS, SVG.
Markdown is a simple documentation markup language that implements the “core” formatting features you find in HTML. It makes it very easy to create simple documentation files (the first version of…
Diagrammelemente werden hier mit Tastatur und einer einfachen Grammatik beschrieben = bessere Usability gegenüber anderen Klicki-Bunti-CASE-Tools; Fehlende Elemente lassen sich schnell direkt in UMLet mit Java programmieren. Ansonsten: http://astah.change-vision.com/en/index.html (formerly known as JUDE)
Papyrus is aiming at providing an integrated and user-consumable environment for editing any kind of EMF model and particularly supporting UML and related modeling languages such as SysML and MARTE. Papyrus provides diagram editors for EMF-based modeling languages amongst them UML 2 and SysML and the glue required for integrating these editors (GMF-based or not) with other MBD and MDSD tools.
Papyrus also offers a very advanced support of UML profiles that enables users to define editors for DSLs based on the UML 2 standard. The main feature of Papyrus regarding this latter point is a set of very powerful customization mechanisms which can be leveraged to create user-defined Papyrus perspectives and give it the same look and feel as a "pure" DSL editor.