First install Virtualbox

1.  `sudo pico /etc/apt/sources.list.d/virtualbox.list`
2.  Add `deb http://download.virtualbox.org/virtualbox/debian saucy contrib non-free`
3.  `wget -q http://download.virtualbox.org/virtualbox/debian/oracle_vbox.asc -O- | sudo apt-key add -`
4.  `sudo apt-get update`
5.  `sudo apt-get install dkms unzip`
6.  `sudo apt-get install virtualbox-4.3 --no-install-recommends`
7.  `wget http://download.virtualbox.org/virtualbox/4.3.6/Oracle_VM_VirtualBox_Extension_Pack-4.3.6.vbox-extpack`
8.  `sudo VBoxManage extpack install Oracle_VM_VirtualBox_Extension_Pack-4.3.6.vbox-extpack`

Now to install phpVirtualbox

1.  `sudo apt-get install apache2 php5 libapache2-mod-php5`
1.  `sudo service apache2 restart`
1.  `sudo adduser --ingroup vboxusers vbox` and enter a password
1.  `wget 'http://downloads.sourceforge.net/project/phpvirtualbox/phpvirtualbox-4.3-1.zip' -O phpvirtualbox.zip`
1.  `sudo unzip phpvirtualbox.zip -d /var/www`
1.  `cd /var/www/phpvirtualbox-4.3-1`
1.  `sudo mv config.php-example config.php`
1.  `sudo pico config.php` and make `$username` and `$password` match the user you created earlier
1.  Also add this line to disable phpVirtualbox's authentication `var $noAuth = true;`
1.  `sudo pico /etc/default/virtualbox`
1.  Add `VBOXWEB_USER=vbox`
1.  `sudo /etc/init.d/vboxweb-service start`
1.  In a browser, go to `http://your-server/phpvirtualbox-4.3-1`