A couple of departments with large lists have asked about using the lists to invite students (or folks who are on their lists for whatever reason) to some events.  
What settings ("Attachments= Yes" I know about) would be needed for this?  I suspect the "Reply-To= " needs to be set, and specifically such that it does not go to the list and the proper "Reply-To: " mail header is created.  The concern came up when this was done a few days ago and one person declined, resulting in the entire meeting effectively being cancelled.  I don't say this is a great use of the listserver, but the issue has come up and now has again, so ...

--Joe