UML Designer - UML Designer provides a set of common diagrams to work with UML 2.5 models.
Xmind - Xmind is a brainstorming and mind mapping application.
Diagramo - Diagramo is an online flowchart software - diagrams (create, edit and share)
MindManager - With MindManager, flexible mind maps promote freeform thinking and quick organization of ideas, so creativity and productivity can live in harmony.
ARIS Express - ARIS Express is based on the proven ARIS methodology and industry standards.
MindMeister - Create, share and collaboratively work on mind maps with MindMeister, the leading online mind mapping software. Includes apps for iPhone, iPad and Android.