openNebula
Key Features http://opennebula.org/about:keyfeatures
Interface for Cloud Consumers
Service Management and Catalog
Interface for Administrators and Advaced Users
Appliance Marketplace
Chargeback
Capacity and Performance Management
High Availability and Business Continuitiy
Virtual Infrastructure Management and Orchestration
External Cloud Connector
Platform
Security
Integration with third-party tools
Licensing
Upgrade Process
Quality Assurance
Product Support