I had the pleasure of meeting Steve Pick from Celtx at the CT Film Festival and learned more about their product, which Saxon Mills used for the pre-production of The Oligarch Duplicity (due in Sept 2009). It’s a great tool and it’s free; definitely worth trying out. For a small fee there are a number of enhanced collaboration tools, etc. Take a look and get to meet one of the really excellent people from this company in Newfoundland.