4. Ubuntu Server 12.10
October saw the release of Ubuntu Server 12.10, the latest version of Canonical's open source server software that now includes the "Folsom" release of OpenStack. What's Folsom, you ask? That's the sixth release of the OpenStack cloud infrastructure platform, and it provides multitenancy and user-controlled self-service cloud deployment, better customization features and the ability to boot directly from block storage devices.