A contact level document repository
Each contact may have its own document repository. A document repository allows the users to upload, download, search or delete documents to/from any contact.
Version Management
An efficient version management system to keep track of the previous versions of the files. You could also Vault or Label a Document Folder.

Another unique addition is the 'Admin' tool, which allows the administrator to lock, unlock or destroy any documents.
A user can check out or check in any documents from a project
Custom Metadata
If required, more custom metadata fields can be added into files or folders; a feature for advanced users.