Recoll - Open Source Search Tool

This package is a personal full text search package which is based on a very strong backend (Xapian), for which it provides an easy to use and feature-rich interface. Avaliable through repositories.

Catfish

Open source File searching tool

Catfish is a versatile file searching tool. Catfish is a search GUI powered by locate and find behind the scenes, with auto-completion from Zeitgeist and locate. The advanced options allow filtering by date and file type. The interface is intentionally lightweight and simple, using only GTK+.

Conduit - Open Source Sync Tool

If you’re using GNOME, Conduit is an open source app that allows the user to synchronize information to and from various destinations. This is an open source file synchronization tool synchronizes files, photos, emails, contacts, etc to another computer or device.

Alfresco - Open Source Document Management

Alfresco includes a content repository, an out-of-the-box web portal framework for managing and using standard portal content, a CIFS interface that provides file system compatibility on Microsoft Windows and Unix-like operating systems, a web content management system capable of virtualizing webapps and static sites via Apache Tomcat, Lucene indexing, and Activity workflow. The Alfresco system is developed using Java technology. Alfresco comes in three flavors. Alfresco Community Edition is free software, LGPL licensed open source and open standards. Alfresco Enterprise Edition is commercially & proprietary licensed open source, open standards and enterprise scale. Its design is geared towards users who require a high degree of modularity and scalable performance.