mix it up - View this location on map 'las vegas night life's latest invention is the ultralounge, a dance club and cocktail lounge hybrid, where swanky dress codes are enforced, cleavage is on display and hefty cover charges deter the hoi polloi. mix ( 877-632-7800), the newest and hippest of the breed, is on the 64th floor of the sleek thehotel at mandalay bay a dark-brown leather atrium with stunning views of the strip. if you want a seat in a lounge on an outside deck, make reservations and be prepared to pay at least $300 for bottle service that's a bottle of liquor and some mixers. ($25 cover after 10 p.m. on weekends.)'' New York Times 3950 las vegas boulevard south, Las Vegas, NV Nightlife

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