It would be usefull to be able to save a topic if you have not the time to finish it right now. Of course others wouldn't be able to see that post.
I use that feature quit often in gmail, because it is easy and fast to use, and I can continue were I left writing, when I come back. It also make me feel safe that a long post won't get lost by a Windows crash or the like, especially when I make a long post. Gmail has even a auto-save feature since a week now.

i believe an auto save would be a good idea. It would auto save per/ x mins configurable in the ACP.

Then if you go away from the topic and either press the 'Add Reply' or 'New Topic' buttons the post would auto appear in the window.

The info would then be removed from your 'stored post' if you actually submit the reply or topic.

or it could tell you "You have xx no. of saved topics/posts"

I still think it would be usefull ...

If I understand correctly, the notepad in the UserCP could be used for this.

An optional auto saving the post to the server as it is being written would be great. (Using AJAX ?)
Members do write long messages on my forum and I and members have lost messages.
I believe that this would be a very popular feature.
Thank you!

I think this is a great idea and use it all the time with GMail but im confused how it would work storing it server side and how you would control it. For example if you had a board which contained thousands of members and each of those saved many posts without posting them surely it would still hold up part of your db. You would then need to include some sort of pruning features for those that havent posted the saved item in so long.

With Gmail obviously looking at what they offer they have no worries about space demands but what about those people with only small db allowances it could cause problems.

I don't think this should be a feature - users would forget their draft posts and it'd be just confusing for those who didn't understand the feature - we have the UserCP notepad.