My Ultrabook has unfortunately only two USB ports that - are each mounted on the right and on the left side of the computer - stupidly. Typically, DVD burners are shipped with a USB adapter cable in Y shape, ie a cable branch is for the data required for the other extra power supply. This works only if you have two free USB ports on one side of the computer, since the USB cable branches usually be relatively short. In my case that was not possible, unfortunately, and so far I have been looking for ages for such a solution.
And why should you occupy two USB ports, if it can be done with one?
Here the Samsung developers have developed a truly energy-efficient, lightweight and quiet machine.