I spent some time over the past few days copying my unedited second novel into Celtx to see how it works.
Now they have specific novel support, and things are much better. Celtx gave me that for writing screenplays, but fell short for writing novels. I've always wanted a program just for writing - one program to rule them all, if you will. Finally, I had a simple text file for storing notes on future ideas that hadn't found their way into the novel yet. Next I have a sort of ad hoc database, stored in a multi-page spreadsheet in OpenOffice.Org's Calc - one sheet for a chapter list and summary, one for character details, and a third for keeping track of revision history. First I have the actual novel, written in OpenOffice.Org's Writer. Up to now, I've been using almost ancient tools to write my stories (ancient in computer terms, not ancient as in 'abacus').
Well, it just got that attention in the new version 2.9 that was released on February 8, 2011. I've always thought this program was almost perfect for novels.
There are several very cool features in Celtx like a built-in database for keeping track of character details, an index card view that makes reordering scenes easy, and an easy PDF export. My brother and I wrote a screenplay using it, and I've used it to write the audio/visual scripts that later became the promo and tutorial movies for my games. A few years ago I found an open source script writing program called Celtx.