Free as in lunch
Matt Davis, video producer and teacher sent me a link to Celtx – a free software suite for screenwriters, directors and producers for Macs and PCs.
You write your outline in the text editor; fill in index cards; write scripts; produce character, prop and location lists; organise storyboards and schedule your production.
The software is free. The publishers make money by selling web services to film makers. Looks like a good deal.