Another free virtualization tool
I have used VMware to create a virtual machine in Ubuntu before but recently I came across another free virtualization tool called VirtualBox which is open source under under the terms of the GNU General Public License (GPL).
The download is just under 15 MB and you can find a step by step tutorial on how to install VirtualBox on Ubuntu on this site. I found the step by step instructions quite straight-forward.
One step that I have to mention here is that to give myself permission to use VirtualBox I had to go the System menu then selected Administration and then added myself as user of the application through the Users and Groups sub menu.
I should also mention that VirtualBox is also available for Windows and Intel Macs.