The latest version of Celtx has a free "cloud" function. They used to have a pay-service where you could store and - if you wanted to - share your script. Now this service is free and included in what so popular is called a Cloud.
One of the great advantages with Celtx in my opinion is the possibility to embed all your project files into the Celtx file. I have my mindmaps, my SuperNotecard-file, my notes, my links, older versions, everything, in one file. I love it.
So it was with a certain frustration I realized that I could only access the actual script from within the editor in the Cloud. I think I should be able to access all files embedded; Not that they should be able to be opened, but downloadable.
The editor in the Cloud was also a disappointment.
But, there is another side of the coin: it is free, and all I need to do is open the file in the Cloud in my locally installed Celtx desktop application and all works as I'm used to. I don't need to transport a SD-card around, risking to loose it, any longer. All I need to do, on any computer with Celtx installed, is to open the program and select the file from the Cloud.
After using this for awhile I just love it. It is very handy to have the files so easy accessible.
I've not yet tried it, but it is possible to invite others to read or edit a script and give comments. As far as I have seen the comments are for the whole script, so it might not be that much difference from sending a pdf and get notes in return. On the other hand you can work more directly, shorten the time from rewrite to read. I'll test this function when I have the first draft of The Power of Bitterness ready.