On its own, tequila is plenty potent (See: Joe Nichols' "Tequila Makes Her Clothes Fall Off.") With artificial flavors and sugars, it's a recipe for a hangover from hell. The exception: Cactus' Patron Agave Margarita. The bartenders at this popular Southwestern restaurant steer clear of Triple Sec and simple syrup and opt for Patron, fresh-pressed lime juice, and organic agave nectar, shaken and strained into a martini glass. The resulting margarita, refreshing with subtle honey-like notes, tastes almost healthy, and will turn you off neon-green, sickly-sweet slop for the rest of your drinking days. ERIKA HOBART 4220 E. Madison St., 324-4140; 2820 Alki Ave. S.W., 933-6000