Valve oh Valve , what a wonderful developer you are as, they have just released volume one of the Portal 2 soundtrack for download for free. Head over to the official OST page to get your turret humming, glados, electro genre music and yes I just made that up. They have even conveniently setup Android and iPhone versions for you. So get to it now! Oh and for the people that think this is just a preview of the soundtrack… the download link is to the bottom left.