I have an implementation of `save_config()` already in https://github.com/coddingtonbear/inthe.am/blob/master/inthe_am/taskmanager/models.py#L510, but there are significant down-sides to that implementation that make me more than a little uncomfortable using it in uncontrolled environments -- it will not remember the line order of your config, and it will not preserve comments for you.

Solving those two problems is not immediately obvious to me, but feel free to post a patch.