Noted is a note-taking app that uses a modal interface. This makes it super easy to manipulate outlines - quickly move lines around, reindent them, etc.

You can use the app here: https://noted.herokuapp.com/

Noted doesn't require anything special to run that isn't included in the gemfile. Just make sure you have Rails and preferably RVM and run:

rvm gemset create noted
rvm gemset use noted
bundle install
rails s

rake spec will run acceptance tests in Selenium (assuming you have Firefox installed).