The Official Portal 2 Website now offers "Songs to Test By: Volume 2," the free second installment in the soundtrack for Portal 2, their puzzle/platformer sequel. Word is: "Give your ears the gift of sound and let them relive the glory days of testing in full fidelity, without the distracting hisses and pops that accompany being submerged in acid. Songs to Test By: Volume 2 (of 3) is now available for download. Plus: Free!" The download is available on this page.