This is not a completely fleshed out idea but feel free to add anything else that it could be. CF BBS has an amazing history of great threads and great posters. We also have an ever growing populace who do not know the history around here. With a subform like this past great threads can be discussed without flooding other forums. If a thread gets necro bumped it can be moved here and also posters can do best of profiles on favorite threads or posters (LHutz amirite?) I don't know if this is something anyone would like but from time to time I enjoy rereading posts that take me down memory lane. And even maybe doing poster profiles where a select poster has some of his greatest posts remembered. It may be a bit corny, but I would read this subform daily, especially with some of the garbage in most forums now.
Honestly, I think that subforum would be empty. New fans won't be interested enough to carry on a discussion with tinman in a new forum. GARM will have to do. my $0.02.
If you create a collection of the classic threads, those become the legacy of the forum. You're putting those threads on display and saying, "this is what we are and what we choose to remember about ourselves." For some reason, I don't think Clutch wants threads about "SCK washing his dirty peen in the sink" and the like to be the things about Clutchfans that are prominently put on display