Text 2 Mind Map is a free, online-based outline tool great for concept mapping and pre-writing. It is easy to use, as it organizes hierarchies using tabs/indents in a list, and automatically generating a colorful (and editable graphic). I's even free to grab your final product (into a PDF or JPEG). Some editing features include colors, fonts and "locking" of branches.
Supervisor of Instructional Technology, Park Ridge High School