It allows you to easily access your VMs directly from Unity Dash
The Ubuntu Virtual Machines Lens is an Unity Lens that allows users to easily list and access and start their virtual machines created via the VirtualBox virtualization software.Ubuntu Virtual Machines Lens allows users who use lots of VMs to quickly open a desired OS installed in a virtual machine.
To install the Unity Virtual Machines Lens plugin in your Ubuntu operating system, open a terminal window (hit the CTRL+ALT+T key combination) and paste the following commands (one by one, hitting Enter after each one):
sudo add-apt-repository ppa:scopes-packagers/ppa
sudo apt-get update && sudo apt-get -y install unity-lens-vm
You will need to restart your session after the installation. This Lens is available only for the Ubuntu 12.04 LTS (Precise Pangolin) operating system.