Restrict Access Of A Document

At the moment I have a blog that I use the Download Protect plugin to protect certain documents so that only members of the site can see them.

Is there a plugin that I could use that would not only protect a document from just members but one that would allow me to specify which members were allowed access to the specific document?

I am happy with Download Protect for all but one of my documents. With one specific document I would like to restrict access to members that are mentioned on it, as all of the members will not be mentioned.