Cayra

Cayra is a pretty awesome program. It allows you to quickly make "mindmaps."

• A mind map is a diagram used to represent words, ideas, tasks or other items linked to and arranged radially around a central key word or idea. It is used to generate, visualize, structure and classify ideas, and as an aid in study, organization, problem solving, decision making, and writing. - http://en.wikipedia.org/wiki/Mindmaps
  

Now I can easily make non-linear to do lists!

Cayra is free to download, though you need to have Microsoft .NET Framework 3.0 installed.