Attachment Categories?

[thenetbox]

Currently the vb4 attachment manager has a way for users to personal create categories for storing their attachments. Has anyone gotten it so the admin can define universal categories for all users? For example, currently when a new user opens up attachment manager, there is only
+Home

But what if there could already be

+Home
++Birds
++Balloons
++Planes
++FlyingHippos

It would probably have to be a plugin but I was wondering if anyone has already made some progress on something like this.

Thanks :D