When I worked on Empty Bowl I wrote some playwrighting extensions for MediaWiki. This lets you write scripts quite easily. You get easy revisioning and diffs. The scripts look something like this:

Seth 
The girl is not the problem. This house- I won't marry.

Laurel enters

Laurel 
Sure you will Seth.
 

And when you view or print them they look like this:

Seth

The girl is not the problem. This house- I won’t marry.

_(Laurel enters)

_

Laurel

Sure you will Seth.

	Act I
	Scene I
	Character Name
	Stage Direction on its own line
	Inline Stage Direction within a line

I have no plans to keep developing this, but I’m open to writing a couple more plugins if anyone wants them. I’m open to farming it out to some source control system if anyone else would like to keep developing.

Download Mediawiki Playwrighting Extension