When I see $type I intuitively think "item type" which is {album,photo,movie}.  But I see in File_Proxy that we consider $type to be one of var/{albums,thumbs,resizes}.  That was fine in File_Proxy but as soon as we put it in the item helper I think we have a conflict.

I think we need a new conceptual name for var/{albums,thumbs,resizes}.  The creative side of my brain isn't firing.  Maybe $file_type?