YouTube user Marflus1 has created this musical gem, which is described as follows:
An Arrangement of "Still Alive" from Portal, produced using the Wintersday Bell and Pipe Organ in Guild Wars 2, a little bit of pitch editing in Audacity, and an awful lot of time in Adobe Premiere Pro.
Whatever it takes!
Marflus1 previously figured out how to wring "Billie Jean" out of Guild Wars 2.
Portal's "Still Alive" in Guild Wars 2 [YouTube]