work simultaneously on Mac and Windows

We are two writers planning on writing a book together, One of us is a Mac user and the other still a Windows user. Is it possible to write on the same book-project simultaneously on a Windows and Mac computer respectively and then sync and see the differences if we have worked on the same part of the book?
Is it possible at all to write on a Mac and a Windows computer and save to the cloud (eg Dropbox) and pick the files up with the other computer and continue working?

Hi,

See

and

There may be other threads on collaborating generally and collaborating across platforms.

HTH

Mr X

EDIT Oh, not ‘simultaneously’. You have to manage when each of you works on it. And have a look at Cubby as an alternative to Dropbox; it has several advantages to my mind, but, importantly in this situation, for a Mac user, it sends a message through Growl when files in a shared ‘cubby’ are changed on the other computer, importantly when the user.lock file is moved to trash at the end of the other person’s editing session. For me, it helps to know if my collaborator is working on it so I don’t try at the same time.