Teedy

Teedy is a document management system that keeps documents organized by tags rather than by deep folder trees. It does OCR on uploads, full-text search across PDF, office and image files, Dublin Core metadata with custom fields, a workflow system, comments, an audit log, sharing by link and an API, plus a mobile client.

Small offices use it for contracts, invoices and shared procedures that several people need to find quickly.

Hosting it on your own server keeps the documents and their access rules inside the building, there is no per-user charge, and the file store and database can be copied and restored with standard tools.