I noticed MyBB Source had a mod for allowing forums to be accessible through direct URL linking only, called [No Show
]. But it was removed due to various bugs. This tutorial allows you to emulate the same effect.
Go to ACP -> Forums & Posts -> Forum Management
Click "Add New Forum".
Set the type to "Category". Title doesn't matter too much, though you should make it related to the forums you wish to hide.
Now, for usergroup permissions, set EVERYONE
's "Can view?" permissions to an unchecked box. It should look like the below screenshot for all users.
Now, if you haven't already created the forum that you wish to hide, do that now. If you have, move it to the category you just created. Once you've created and/or moved the forum you wish to hide, edit it.
For it's permissions, set every usergroup you want to be able to view that forum (but only access it through direct URL) to a checked box for "Can view?")
NOTE: You will not be able to just create a forum under the category with permissions set to view. Moving or creating a forum under a category copies the category's permissions. You will need to either create the forum under that category, or move a forum already present to the category, and then edit the permissions again once it's there.
If done correctly, both the forum and category will be hidden from view, but the forum will be accessible through direct link.
What are it's uses? Well, Gaming Forums can have semi-professional review sections, cheats sections, etc. Allowing users to browse through such content, but at the same time, not having to group it amongst forums. Get creative, and you can find pretty nice uses.
Enjoy. And please don't post this tutorial without my given permission.