Storyist?-- A powerful story development tool for novelists and screenwriters.
With an intuitive interface that puts you in control, Storyist provides:
* A word processor with a page layout view and support for headers, footers, and style sheets so you can produce submission-ready manuscripts and scripts.
* A storyboard with customizable story sheets so you can track your plot, characters, and settings.
* A project manager with fast, project-wide search capabilities so you can keep your writing organized and accessible.
http://www.storyist.com/features/index.php for details.