Famous line in gaming culture, originating in the Star Fox franchise. The line is commonly associated with the character "Peppy", due to his tendency to instruct the player to perform the maneuver, commonly when a scripted ambush or similar event is occurring. Due to his insistence upon suggesting that Fox "Do a barrel roll!" in so many situations, it has come to be parodied as a panacea for all problems.
In the context of the Star Fox franchise: "Fox, it's an ambush! Do a barrel roll!"
In the context of internet communication: "I can't finish the last level of the campaign! Any tips?" "Do a barrel roll."