Instead of posts, just provide a way to highlight interesting messages. maybe through upvotes

Posts are a bit of an overkill; all I want is to be able to select a message that is interesting or useful, and then have a view of all the messages that were interesting or useful so a) that either they can easily be referenced or b) someone can catch up easily.

Perhaps giving the ability to upvote messages and then show a view of a forum where you can see all the messages that were highlighted this way, either in chronological order or by number of upvotes would be useful for others to catch up on what has been going on in the forum.