Ubuntu's cloud orchestration is called Juju. This set of tools allows one to provsion various machines on a cloud provider such as Amazon's EC2 or a private cloud on something like OpenStack. One can provision services and expand very easily. A little too easily!
Given that I don't have an easy access to EC2 or a OpenStack cloud, I was more interested in being able to spin cloud images locally, holodeck style! Pipe dream? Not really. There is this thing called LXC, or Linux container. This technology is somewhere between chroot or BSD jails and a Virtual Machine. So, using a juju front end, a lxc backend on my local machine, I can spin images up, expand it, and spin it down, and even destroy the environment in a few minutes.
What does it take? Install a few packages on Ubuntu, and a few commands (these spin a WordPress image with a MySQL backend):
juju deploy wordpress
juju deploy mysql
juju add-relation wordpress mysql
juju expose wordpress
and we have a cloud! Read more at: http://www.stgraber.org/2012/05/04/lxc-in-ubuntu-12-04-lts/ and http://askubuntu.com/questions/65359/how-do-i-configure-juju-for-local-usage try it out youself.