graphviz.it
graphviz.it copied to clipboard
Collaborative use of GV.it
trafficstars
If a URL could be provided for a saved diagram and dot code, GV.it could be used collaboratively, enabling two or more people to update a diagram iteratively as part of a discussion or some other collaborative prototyping effort. This would seem to be consistent with your use of the word "fiddle", although you might've been thinking of just a single user there(?) If that could be implemented, it would also provide a very strong differentiator between GV.it and the standard GV app.
It's fairly easy to do it in presenter-listeners (one to many) mode - it's much harder to do it for many editors at a time.