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Vignon is an alcoholic beverage served on Equellus.
Apollo orders this beverage prior to his encounter with Lacerta's lackey, Marco, in the nearby town bar. During his conversation with Red-Eye, the Cylon Centurion under Lacerta's control, Apollo comments that the Cylon wasn't missing out on the drink, despite the fact that he orders another at Lacerta's table (TOS: "The Lost Warrior"). Judging from its name, it is apparently intended to be interpreted as a form of wine by the audience.