Out of all the spirits categories, rum may have the most experimental ethos in the field. There seem to be fewer rules, and the regulations that do appear seem to be flexible and open to a wide range of interpretation. That\u2019s proving to be an exciting thing, yielding some wonderful, unusual bottles to try right now.\r\n\r\nRum can be made from molasses or sugar cane juice; it can be made, distilled and aged in any number of countries, under any number of conditions; even the interpretation of age may vary widely depending on the country of origin.\r\n\r\nFor example, The Rum Cooperative Volume 2 stands out as a delicious example of the magic that can happen when rules are mutable. It\u2019s a mix-and-match triumph. The bulk of the liquid\u2014just over one-third\u2014is an eight-year-old rhum agricole from Martinique, establishing a sturdy base of tropical fruit funk. Roughly one-quarter represents a robust molasses-based 12-year-old \u00adPanama rum, and another one-quarter hails from Mexico\u00ad\u2014a pot-stilled 12-year-old aged in used brandy barrels which adds tones of brown sugar and stone fruit. Smaller amounts of rum from Puerto Rico and Colombia lend complexity.\r\n\r\n\r\n\r\nAnother boundary-\u00adpushing bottling is a rum built using both tropical and continental aging. Until recently, it was generally understood that spirits aged on the continent, namely Scotch or Cognac, were aged under cooler, drier conditions, while spirits aged in tropical conditions, usually rum, are aged under hotter, more humid conditions.\r\n\r\nWhile some rum experts argue that rum should be aged in its country of origin, Cognac house Ferrand bends the rules by transporting tropical-aged rum to France\u2019s Cognac region for a second aging time. Isle of Fiji, a nonvintage rum that will become a permanent part of the Ferrand portfolio, has a caramelized fruit profile that should please rum-lovers, even though it may agitate lovers of rules.\r\nUnconventional rums to look for\r\nAdmiral Rodney HMS Formidable; $130, 96 points. Made with rums aged from nine-12 years, this rich, full-bodied spirit offers brown sugar, caramel and spice aromas. The soft palate balances vanilla sugar and custardy flan with lively citrus, perfect for a dessert pairing. Spiribam.\r\n\r\nPlantation Isle of Fiji Rum; $25, 95 points. The aroma suggests banana bread drizzled with honey and just a whiff of pineapple. The palate magnifies that tropical note, exploding with juicy grilled pineapple and landing lightly with vanilla, coconut and cinnamon tones. Mix into pineapple Daiquiris and Pi\u00f1a Coladas. Distilled and aged two to three years in Fiji, then another year in the cooler climate of France in ex-Ferrand Cognac casks. W.J. Deutsch & Sons. Best Buy.\r\n\r\nRhum Barbancourt Estate Reserve Aged 15 Years; $55, 94 points. Maple, coconut and honey sweetness, even a hint of cookie dough entice nose and palate, finishing gently with warming baking spice and candied orange peel. Made from fresh sugarcane juice. Crillon Importers.\r\n\r\nDos Maderas Selecci\u00f3n Superior Reserve Rum; $60, 94 points. Expect a dark brown hue and rich toffee and espresso aromas. This rich, velvety sipper offers plenty of mocha and fudge, finishing with dusty cocoa and a hint of dried fig that belies PX Sherry is part of the mix. This bottling starts with rums from Barbados and Guyana aged in the Caribbean for 10 years, then transported to Spain for blending with casks of a five-year-old rum that has been finished in PX Sherry casks. Palm Bay International.\r\n\r\nAppleton Estate 8 Year Old Reserve; $29, 93 points. This reserve bottling, released in spring 2020, is intended to commemorate the 250th anniversary of the brand. Complex and smooth, look for an amber hue and mildly funky aroma that mingles banana funk, vanilla and a hint of red fruit. The palate amplifies that fruit, opening with dried cherry, caramelized pineapple and vanilla, drifting into a drying finish laced with nutmeg, clove and coconut. Campari America. Best Buy.\r\n\r\nHidden Harbor White Rum; $35, 93 points. Made for Pittsburgh tiki bar Hidden Harbor, this rum is specially formulated for use in Daiquiris and other tropical cocktails. Most of what's in the bottle (80%) is made by Pittsburgh distillery Maggie's Farm, and the remaining 20% is a blend of Caribbean rums. It's a full-flavored, robust white rum, with a mildly funky aroma and a surprising hint of red fruit jazzed up with ginger and white pepper on the finish. Should stand up nicely to fruit and bold flavors. Allegheny Distilling.\r\n\r\nThe Rum Cooperative Volume 2; $35, 93 points. This delightful tawny sipper opens with aromas of dried apricot, golden raisin, maple syrup and candied ginger, finishing long, spiced and a little sticky. It almost sips like a spiced rum but it's not\u2014just a blend of rums from five different rum-making regions, namely Martinique, Panama, Mexico, Puerto Rico and Colombia, with an age range spanning eight\u201312 years and representing various raw materials and distillation methods. Bully Boy Distillers.\r\n\r\nAbleforth's Rumbullion! Spiced Rum; $35, 91 points. This amber-hued spiced rum is on the sweeter side, with lip-smacking notes of cola, cocoa, cinnamon and cardamom, finishing with a hint of clove and black pepper heat. The producer recommends mixing into a \u201ctraditional navy grog.\u201d Park Street Imports.\r\n\r\nSaison Rum; $28, 91 points. This light and silky sipper from Cognac-maker Jerome Tessendier has a pleasing brown sugar and vanilla bean profile. The elongated finish is laced with cinnamon and nutmeg. Made with a blend of rums from Barbados, Trinidad and Jamaica aged up to five years in American white oak, the blended rum is then finished in Limousin casks in France's Cognac region. Romina Foods, Inc. Best Buy.\r\n\r\nThrasher's Green Spiced Rum; $27, 91 points. Think of this unusual newcomer as a mix between spiced rum and gin, with the usual spice additions mostly replaced by citrusy and herbaceous flavors. Veteran bartender Todd Thrasher uses botanicals grown in his own backyard, including lemon verbena, lemongrass and mint. The aroma is malty and brisk, with a hint of dill, while the palate is slightly sweet, with a mouthwatering citrusy tartness and a hint of coconut that winds into the complex finish laced with ginger and cardamom. Potomac Distilling. Best Buy.