And wouldn't it be great if the summary/tag fields were pulled into the item data grid....instead of having to re-key that stuff...  The Offcie docs and other XML files should be normalized.  TIFFs and other image formats might require more research.

1. Subscriptions that notify the user when a document changes.
2. Subscriptions that notify the user when a new document is added to a specific category.
3. The capability to work as a repository/library of documents and select wether to show the whole library or only certain categories in an instance of a module
4. Restrict the type or types of documents a certain category can hold.

Perhaps this should use a repeater and switch templates based upon the type of content.  As cfrankland pointed out many filetypes have tagged headers which could be read for properties to be displayed....so different templates would be needed.  Something like:  http://www.codeproject.com/aspnet/ObjectRepeater.asp

I'd want to index these properties for searching, but I'm not sure that I'd want to index the entire document contents.  For one reason, image types (or embeded images) could suck up a lot of db--and never be a search "hit."  For another reason, if I wanted the content in HTML, or some central CMS, wouldn't I put it there instead of leaving it in loose files to begin with?  (Not clearly stated, I'll go get some coffee...)  My point is I can see both sides on importing the content--give me a module setting to pick the indexing level: None, FileSystemProperties, DocumentProperties, or FullContent.

That's my point above, there are many ways to secure documents.  Some of these are considered because of the MediumTrust issues, some are chosen because of a desire to link to an existing CMS, some are chosen because of DOD requirements to isolate content storage on boxes other than the webserver... 

I'm not sure how widespread Bo thinks a FileSystemProvider would be used throughout DNN.  To me DNN is a MS ASP.Net product, and so it does assume Windows for the filesystem, and I'm ok with that for the general system.  But for document content, security requires that I MUST target other providers, I cannot leave content anywhere under the IIS site....thus I've written my own documents modules.  Although I cannot release that specific code, I'd love to see this module be able to choose between various mechanisms for retrieving content.