A doctor from Spain recently spent time visiting friends in Belfast. For their hospitality, he treated them to one drink at the Bar at the posh Merchant Hotel. Cheap? Not exactly. It was a $1,400 Mai Tai, the most expensive cocktail in the world, according to the Guinness Book of World Records. A Mai Tai, the token tipple of tiki bars--for the price of a trip to Bora Bora? "It's all about the rum," says Sean Muldoon, the "potation" manager at the opulent hotel bar in northern Ireland. "The presentation may seem like nothing," says Muldoon, referring to the bottle's plain Jane, hand-written label. "But I believe what we have here is something very, very special... This is history in a bottle." Indeed. The J. Wray Nephew 17-year-old rum from Kingston, Jamaica, is the very same golden, pungent, full-bodied rum that inspired "Trader" Vic Bergeron to create the original Mai Tai at his Oakland bar in 1944. It's unclear if this bottle of 17-year is an actual remnant from the sugar estate or a ridiculously limited replica made some time later. Either way, there are only six bottles of the stuff floating around, and the Merchant's bottle, which sleeps in the hotel safe at night, is the only one that's available to the public. Crafty Cocktailing There have always been people with money to burn, but rarely have there been so many exorbitantly priced cocktails at their disposal. Modern day "mixologists" like Muldoon are constantly seeking ways to elevate the art of cocktail making by conjuring their own cordials, syrups and tinctures. They are driven by a public that has become increasingly savvy, and discriminating about what passes their lips, and distillers who keep giving them better and better spirits to work with. Antonio Dandrea, bar manager at the Donovan Bar at Rocco Forte's Brown's Hotel in London, says this puts a lot of pressure on mixologists to constantly push the cocktail envelope. "People are always looking for something different," he says, "something they can't find anywhere else." Hence his lavish $100 truffle martini, which begins with a nubby black truffle from Alba enjoying a 48-hour soak in super premium vodka. For $20 more, he'll mix in some chocolate liqueur, float some double cream across the top and add two slices of fresh truffle. Top Of The Tops Not one for sweet drinks? We scoured bars, casinos, restaurants and lounges around the world to find other decadent libations and discovered they fall into distinct categories. Some, like the famous Ritz sidecar, at the Hotel Ritz in Paris, also deliver gravitas in a glass. This former Guinness record holder features a coveted 1865 Ritz Reserve cognac from Napoleonic times. Other lavish cocktails contain pricey, top-notch--though not necessarily historic--ingredients. The margarita at Isla Restaurant at the Mirage Hotel in Las Vegas is made with smooth Herradura Seleccion Suprema tequila, Grand Marnier 100-Year Anniversary, Cointreau and fresh citrus syrup. An added bonus? It's prepared tableside at the restaurant by Isla's very own "tequila goddess." Sometimes, it's the garnish--not the pour--that sends the price soaring, as in rubies parading as maraschino cherries or a solid-gold swizzle stick. The most famous in that category is the Algonquin Hotel's $10,000 " martini-on-the-rock,"--the "rock" being a 1.52-carat diamond from the hotel jeweller. Serious spirits aficionados, however, dismiss these as choking hazards dreamed up by marketing types. "I may as well serve a cocktail on top of a mink coat and call it my $20,000 sidecar," says Duncan Halden, bar manager at Gordon Ramsey at the London in New York. Though it's not on the menu, he serves a $550 sidecar to connoisseurs upon request that, he says, "out-luxes" the famous version at the Paris Ritz. It features Hennesey Ellipse super premium cognac--poured from a decanter which is specially designed by Tomas Bastide, a designer at Baccarat--and Grand Marnier 150. Out-There Offerings A small but growing category of drinks aren't so much outrageously priced as they are simply outrageous. Piggybacking on the new "molecular" trend in gastronomy, some mixologists, including those at Below-Zero Nitro Bar at Barton G. The Restaurant in Miami are playing "mad scientists" behind the bar. They've been infusing cocktails with liquid nitrogen, which not only freezes the alcohol but also causes it to intensify as it melts. The classic nitro-tini features Ciroc Snap Frost vodka, a frozen vermouth swizzle stick and olive, and frostbitten blue cheese pearls. The newer sin-sation features a rose bud stem encased in frozen Absolut Vanilla, which is doused with rose petal nectar (undiluted juice from pressed petals) and premium champagne. "The alcohol gets as cold as the surface of planet Pluto," says restaurateur and event planner Barton G. Weiss, and, of course, there is a fog factor that adds to the effect. Weiss says he's just responding to the customer's constant desire "to be wowed." Leave it to Weiss to put "wow" on ice. Just last week he threw an 80th birthday party in the middle of the Orange Bowl Stadium complete with a marching band and a parade float studded with sweets. "It's an exciting time to be in the business because there really are no boundaries," he says. Whenever one of the nitro-tinis is prepared, cell phones come out of purses and breast pockets. "More than just a drink," he says, "these are a real conversation piece." And, topping out at $32 they're a veritable bargain.