Ability for Messages to Appear in Two Forums?

[danielkomen]

I'm not sure if this is the right forum for this but I don't seem able to post in any other forums because I don't have vbulletin yet:

Is there a hack for vbulletin so that some posts can appear in two forums?

Currently, I have one forum on my site, but I want to go to a multiple category forum like vbulletin. But I want there to be a main forum that has posts from some of the other category forums as well. So these posts would show u pin the main forum and the category forum as well.

Is this a feature our would it be easy to implement without hampering performance>

Threads appear to just have a thread number:
http://www.vbulletin.com/forum/showthread.php?t=142051

so I assume there is a database that associates each thread with a category(Forum). I don't think it would be that much more difficult to have this field hold 2 category fields (mysql set field) but I guess this could really hamper performance. I think this would be very similar to subforums. That would be a good second best alternative. However, I don't want a true subforum system As I want some select posts that are designated by the poster to appear in the main forum not every single post.

So is this a supported hack? If not would it really hamper performance?