[BasilFawlty]

UPDATE: I figured out how to do exactly what I wanted to do without a Modification, so I thought I'd share it here in case someone else wants to do this. It was really quite easy (I'm using VB 4.2.0 Patch Level 2 by the way). I wanted to have a category of forums for "Classifieds" where the classifieds forums did not show up in the main forums listing but instead show up under a separate TAB. Here's what I did:

First, I went to Admin CP >> Forums & Moderators >> Forum Manager and created a "Category Forum" like "My Classified Forums". I set "Act as Forum" = "No" so this would be a category. Then I set "Forum is Active?" = "No" so that it would not show in my main forums list, but as the description box states, it would still be accessible if you know the URL. (I had to make it active temporarily so I could go to it and copy the URL).

Next, I created several "For Sale" forums under this new category and set "Act as Forum" and "Forum is Active" both = Yes. (But they don't show up in the main forums page because the category they are under doesn't show up.

Finally, I created a Tab in the Navigation Manager that points to the URL of the "Classifieds" Category.

That's all there was too it. Now, I have a tab called Classifieds and when I click it I go to the classified forums, just like how here on VB.org the "Mods" and "Styles" tabs take you to separate categories of forums.