Alfresco (ECM)

Alfresco has had a great year taking on Sharepoint, landing new deals with Adobe to be the content management component in Adobe LiveCycle and also to be the CMS behind Acrobat.com, a free online document creation, sharing and collaboration environment. Alfesco was also named by Gartner in its ECM Magic Quadrant report in the niche player category. 

It can handle ECM or WCM, depending on your needs and recently added a new set of Web 2.0 collaboration tools. You can download a fully functional package for free or you can get a yearly subscription that gives you access to updates and support, an approach that should appeal to enterprise users looking for more support. Alfresco also sells consulting and training services. For an overview of Alfresco licensing details, see the License page on the Alfresco web site.