Are you talking about a way to store documents in a database and search them?

[link|http://www.hummingbird.com/|[link|http://www.hummingbird.com/|http://www.hummingbird.com/]] They used to have a product named DocsOpen that allowed integration with MS-Word, Excel, etc that kept the versions of the documents and kept copies of the older ones in a database that was searchable. They renamed the thing and I forgot what the new name was.

You could always try to build one in Linux, copy the document file to a network location and point the database to it and give each file a unique name. Code it by keywords, client and matter numbers, etc.