Okay, I wanted to have it on my forums so I could have a certain group that can only access parts of the ACP. I wanted it so these moderators would be able to change around the forums, skins, and user groups. I think this feature should be implemented in 2.2.

Restriced ACP is in 2.1.x already. it's on the front page of the ACP.

Yeah, just figured it out.