celtx

Celtx is an open-source pre-production app, based on the Mozilla engine (ala Songbird, Firefox, etc.).

The screenwriting component utilizes familiar Tab and Enter prompts for switching between formats, with keyboard shortcuts as well (i.e., cntl/cmnd-1 = Scene Heading, cntl/cmnd 2 = Action, etc.). Celtx takes a Project-Based approach, allowing the user to keep outlines, saved images and/or sounds, etc., as well as multiple drafts of the screenplay itself, all in one file. Multiple components can be open simultaneously, using a familiar “tabbed” interface, ala Firefox, Mozilla, and most modern web browsers.

Other features include index cards, dual dialog, storyboarding, stageplay, audio play, and AV script formats, scheduling, calendar, reports, templates, and snapshots (versioning). The application is very stable and user-friendly.

Currently pre-1.0 (now at version 0.9.9.7), this app shows more promise with each release, squashing bugs and steadily adding features. The developers are very active in the forums, and responsive to user-input. It is available for free download on the Big Three platforms (with complete file compatibility/interoperability): Mac, Windows, and Linux.