Ansible to automate installation of bigbluebutton (some tasks need to be run manually, see comments in playbook) according to:
http://code.google.com/p/bigbluebutton/wiki/081InstallationUbuntu
Playbook to configure ubuntu desktop (including xen); after the installation of ubuntu desktop (12.04 and 14.04 - LTS), install ansible and run ansible-playbook ubuntu.yml to configure everything (well, you need to customize it according to your own requirements)