Is there a modification - or way to enable present features - for Private Messages, that would enable a recipient to make a particular message publicly viewable? I envision having it post as the first post in a new thread (perhaps use of the feature could restrict the forum to which these post in the first place . . . ) with follow up conversation by the person who made the PM public, and the rest of the community.
I've seen communities where the PM system is abused as a medium to bully and silence community members (as I'm sure we all have) and it seems like it might be a valuable tool in the right, mostly-self-policing community. If people knew their PM could be made public, they would think twice about what they say under the "cover" of the PM system. It wouldn't be right for every community, but it would be great in community that are otherwise good with self-censure when a member steps out of line.
I don't think there is anything like this. You could just disable the PM system for certain usergroups.