If the humble hack 'n slash game Bastion needed one thing to take it from great to awesome, it was more Portal turrets. In a quest exclusive to the Steam version of Bastion, The Kid uses a Gel Cannister marked with the Aperture Science logo that contains "a viscous substance of unknown origin" to portal friendly sentry turrets into battle. The result is pretty glorious, as you can see in the video above.
If it's any consolation, the turret at the end seems just as confused about its existence in Bastion as we were, but it's not nearly as giddy with excitement.
[Thanks for the video, Michael!]