While we're certainly appreciative of all the efforts various sects of monks have made in the advancement of knowledge throughout history, how about their work in the time-honored tradition of throwing one back? Praise be to the Carthusians then, a French sect responsible for the distillation of Chartreuse for over 400 years. The most notable variety, Green Chartreuse, is a liqueur made from some 130 herbs and plants, the full extent of which are only known by two or three people at any given time (although the exact recipe has changed once or twice). It's kind of like "The Da Vinci Code" of drinking.
The spirit has a distinctly sweet, herbaceous and medicinal flavor (people thought booze was medicine until relatively recently), with an assertive anise note. It's a worthy addition to your home shelf if for nothing else than mixing the outstanding Prohibition-era cocktail The Last Word, made with equal parts gin, lime juice, Green Chartreuse and Maraschino liqueur. Stellar variations abound, like the Final Ward, invented by Phil Ward at Death and Company in New York City, which substitutes rye for gin and lemon juice for lime.
A second variety of the liqueur, Yellow Chartreuse, is made with a similar recipe, but the addition of honey and saffron make it brighter and sweeter, and provide the striking yellow color. Its lower proof (80 instead of 110) also makes for less boozy mixing with gin, as in another Prohibition-era standout, the Alaska (1 ½ ounces gin, ¾ ounce Yellow Chartreuse, 2 dashes orange bitters).
If you've already taken to the flavor (admittedly, not for everyone) skip ahead to Chartreuse V.E.P. (Vieillissement Exceptionnellement Prolongé). Available in both colors, it's the same recipes aged even longer in oak. At around $20 a glass, it doesn't make sense to mix with it, but it does make for a more mellow approach to the densely concentrated herb profile, with less of the spicy burn. Old-timers suggest drinking it cold as a digestif, but at 108 proof you'll still want to drink it slowly, which will help you savor the full bounty of flavors. It just might be a religious experience.