Mind map architect program is good tool for brainstorming for single person just as for team. Mind mapping tools can be usable for todo lists, notes, or work planning.
Open-source, cross-platform 3D rendering engine for .NET and Mono. The Axiom Engine is a high-performance C# port of the powerful OGRE engine and provides full support for DirectX, OpenGL and XNA on Windows, Linux, Android, iPhone and Windows Phone.
J-gramS is a diagram editor that uses Java and SWT. Similar to idraw and xfig it focuses on creating diagrams easily without a complicated user interface. Diagrams produced by J-gramS are saved as SVG or a number of image formats.