Open Source Document Management Solution: Alfresco

Alfresco: Product
whoa! this looks like it will outperform Documentum... If you're rolling a new DMS for your company look at this technology preview NOW!

Alfresco is the first open source enterprise-scale content management system that includes a modern content repository, an out-of-the-box portal framework for managing and using content designed to work with standard portals, and a groundbreaking Common Internet File System (CIFS) interface that provides Microsoft Windows file system compatibility. Alfresco takes the lessons of building content management systems for the last 15 years and applied them to build an open source content management system that is easier to use, more scalable and more adaptable. The Alfresco system is developed using the latest Java technologies including JBoss 4.0, JBoss Portal 2.0, Spring 1.2, Hibernate 3.0, MyFaces 1.0, Lucene 1.4 and Java 1.5.