Be able to make a post immune to pruning without making it special.

[Crystallas]

This just makes it easier to archive a forum IMHO. Its a feature that I would use constantly, especially when you start to see 4 or 5 years worth of posts, and you try to salvage good info on the fly.

So what I would like to see is a feature that wont prune a post that a moderator finds useful and marks the post(via reply or editing main post) a "unprunable." 

I have been asked to admin another forum with 4 years worth of posts. The original owner just had a basic phpbb setup with little knowledge of how to do anything with the forum. I recently converted it to SMF. We need to shrink the DB about 100mb, and thats when I thought it would be a much better idea to just go through posts and set them as unprunable. Instead of filtering out, adding sections, and having to deal with this every time the forum needs to shave a few pounds.