Old Overcoat

Despite being produced by Jimkin Bearhugger's Whiskey, it is not a whisky, but a blue liquid with gold flakes, probably classed as a liqueur. It is not, apparently, any more popular than you'd expect. It's a classic example of those bottles sitting on a high shelf over most bars, glowing bright colors but never being poured.

The drink appears in the futuristic universe of The Dark Side of the Sun. Isaac comments that with two drinks of Old Overcoat, you lift off on a pillar of flame.

Annotation

On Roundworld, the usual jocular version of the name of Old Overholt, not a liqueur but one of the few rye whiskeys still made in and widely available in the USA.