A 'spacer's flip' is a class of dessert drink related to the spacer's delight. A spacer's flip is less a unique beverage than a tradition associated with the professional spacer's never-ending quest to improve famously bland CELSS algae meals. The beverage is considered a rite of passage in the same way that crushed hats are among combat cruiser crews: long stretches of hard labor away from the comforts of traditional food and booze inculcate the drinker to the beverage's blandness, so knowing the best ways to make an drink the flip are a sign of veterancy.
Spacer's Delight is traditionally a layered drink made with gin, pulpy starbell liqueur, and extra-iodized salt. In addition to emulating the colors of the Cobalt Protectorate ensign, these ingredients hearken back to the early days of atomic rocketry (i.e. iodine from fallout exposure) and are thus close to the hearts of all Evermornan star pilots. There's only one problem with the popularity of this drink: starbell plants are rare in spacecraft and orbital installations due to how difficult it can be to grow them beyond Planet Evermorn. Spacers, however, are an ingenious sort and loathe to let tradition die because of some paltry issue like the lack of simple raw materials. To create a spacer's flip, a combination of algae feedstocks from a vessel's closed ecological life support system can be fermented and combined to create an alcoholic beverage that vaguely resembles the flavor and consistency - if not the true composition - of a spacer's delight. Strains with different sugar and salt compositions are muddled together to loosely mimic the fruity and herbaceous elements of the drink, while lysed batches are exposed to yeast to induce fermentation. The broken cellulose walls of the algae used in the fermentation process settle out of the mixture under centrifugal gravity, providing the 'starbell pulp' in the drink. The blending process results in a thicker, more frothy mixture overall, leading to this drink being known as a flip rather than as a traditional cocktail.
Most people not accustomed to eating algae will balk at the prospect of drinking a bitter, slimy mixture of green alcohol that came from what might be considered the ship's sewage system. Spacers, however, know well that everything on a spacecraft is already recycled in this manner; for these people, imagining the old flavor as one drinks is the more relevant issue. Making the mental leap to enjoying the beverage outright is something that only comes with frequent exposure, and, thus, enjoying spacer's flips is considered a sign of professional experience. Command staff and others with great experience may outwardly profess a desire to keep their crew sober through-and-through, but will also distribute the best 'recipies' to life support officers they trust to make the moonshine without rendering the drinkers blind. Strains of CELSS algae with exotic flavor profiles are common trade goods between asteroid colonists and visiting ship crews, and those with starbell-like fruit flavors are unusually popular. Artifical exografts of starbell cones are also popular, but as these require specialized equipment to maintain, they are not as common as dried spirulina that taste close enough to the 'real deal.'