This is funny, because I was thinking of putting Mephit on SourceForge. Thinking very seriously, but when I saw this topic I decided to wait a bit and see what comes out of this.
However, let's not jump to conclusions. A collaborated project would be great, but... what project, exactly? It's no use gathering up and writing together an "online PHP editor". Why? Because nobody really needs an editor in itself. People need an online system to manage the files on their site, to make some changes to their PHP code on a working site, etc.
That's why I see no reason to create an editor that uses a database, as opposed to working on the filesystem. Because if I need to write my scripts first and then deploy them, I may as well use Zend Studio or whatever.
That's why I see no reason doing a technologically advanced, complex, XUL-based solution, because it won't work on the net's most popular (although most buggy

) browser. But XUL is good actually... maybe as an option?
Generally, I see no reason doing a technically advanced system that is actually useless to the end user. And I'm afraid saw a bit of this kind of thinking back at the first part of the contest. Remember that you can't compete with a desktop editor (editing functionality), or with CVS (group work). The only advantage that you can offer is online editing, i.e. live editing. Mephit was actually used to correct/change its own source code, on a running site. And it was much faster than running Putty and then vi through SSH.
Anyway, let's start with the question "what to do", rather than "how to do". I say that to make any such project successful we need:
- directory browsing
- file management (creating, deleting, blah, blah)
- upload and download (also compressed directories)
- viewing files of different types, not only PHP
- editing text files
- special features for editing PHP
I would like to see some demos of the applications submitted to the last contest, to see what they actually offer. Mephit is still available, so you can all see what it does. Mephit has only basic PHP editing functionality, and upload/download is not implemented in anything I've seen at the contest, but the rest is already done, and done well.
For me it would be simplest if I put it on SourceForge and those who wanted to cooperate joined the project. This way it can be started immediately. But I want to know your opinion.