Everybody loves a scrappy underdog when it comes to sports, politics, and dogs. Drink the under-booze at the Independent Spirits Expo, tomorrow night at Astor Center. Now in its 2nd bigger/better year, ISX is a gathering of 16 fledgling spirits that've achieved only modest distribution after years of slavish toil (pulled up by their own hooch-straps). The deal: drop a mere $15 (with sweet promo code -- see below) for 3hrs of open bar, during which you'll guzzle these and many more gut-stoking wonders: Zuidam Gin: A dry gin distilled in the Netherlands but made from globo-sourced ingredients (Italian juniper berries, Moroccan coriander, Spanish angelica root, Indian liquorice root, etc) -- because the Neth's native ingredient isn't legal here. Tuthilltown Spirits: The Upstaters're pouring everything from vanilla-tinged Hudson River Rum and local-corn-fueled Hudson Baby Bourbon, to two signature vodkas: Heart of the Hudson and Spirit of the Hudson, suggesting NY's waterway is so complex it needs two metaphysical abstractions to goad you into midnight calls to your ex. Castries Peanut Cream Liquor: The storied St. Lucian distillery's first US-available spirit is a mix of Madagascan vanilla, roasted peanuts, spices, cream, and St. Lucian rum, all in a disturbingly peanut-shaped vessel. The liqueur's available at Astor Wines; empty bottles will be resold at The Pleasure Chest.