Mural.ly is a new tool (still in beta, launched last week) that is a cross between Prezi and mind maps. It’s easy to use and share what you create (perfect for most students, teachers, and parents) but the real beauty of mural.ly is in its lack of structure.
I love mind maps, so Mural.ly's got me all excited... it's wonderful.
My first board is for my fiction ideas. I have a mile of these, and they're hard to track. Mural.ly will be wonderful for brainstorming fiction.
This program is still in beta, so do be sure that you take screen clips of your boards. Beta software can be temperamental.