I know this is probably not possible but thought that I would ask anyhow. Is there any way to tell what books that I have not used in a collection? I have been working on and off creating several collections (using the wiki, personal ideas and other sources) trying to better organize/utilize my growing library but have a feeling that I still have quite a few resources that can still be utilized in a collection but going through them one-by-one is very tedious and not possible for my time limitations.