Portal 2 Spoilers ahead. » This version of "Cara Mia" isn't as lovely as when it was sung by the turrets in , but it might be even cooler.
This is an A Capella version of Cara Mia, the "turret opera" from late in Portal 2. I don't really know why you'd sing this, but vocalizing music as beeps and boops is a big part of A Capella, so it works just fine. »