Linie is the smoothest, richest aquavit we've ever sipped. Distilled from potatoes, with a robust caraway flavor, it's aged, per Norwegian law, in oak. But the Oslo-based makers of Linie take it even farther—literally—by sending their casks off in the holds of ships, on a 19-week voyage that crosses the equator twice. Along the way, the spirit sloshes around with the movement of the waves, and the barrels—formerly used to store sherry—swell and contract in extremes of heat and humidity, imparting the character of the wood and polishing the flavor, so that the gold-hued liquor tastes rounder and nuttier. While many aquavits overwhelm in cocktails, Linie mixes beautifully, providing a layer of deep, warm, woodsy spice.