Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
Xmind - Xmind is a brainstorming and mind mapping application.
Sketch - Professional digital design for Mac.
MindMeister - Create, share and collaboratively work on mind maps with MindMeister, the leading online mind mapping software. Includes apps for iPhone, iPad and Android.
Adobe Illustrator - Adobe Illustrator is a vector graphics editor.
Viima - Viima is the simple, yet incredibly powerful Agile Innovation Platform that helps you go from ideas to innovations – at the speed and scale of a true innovator.