Las Vegas goes crazy for Labor Day weekend, and none othe than Will.i.am kicked off the party Friday at Encore Beach Club at Encore Las Vegas.

Hundreds of fans were treated to a performance by the singer and his Black Eyed Peas bandmate apl.de.ap.

PHOTOS: Will.i.am Gets The Party Started At Encore Beach Club In Las Vegas

Nicole Scherzinger -- the Pussycat Dolls lead singer-turned-judge on Simon Cowell's new The X Factor -- was so moved that she joined the superstar musician in the DJ booth and showed off some of her sexiest dance moves.

The music and party kept going until sunset and that was just the first afternoon!

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Adrianne Curry left very little to the imagination Saturday as she celebrated her birthday poolside in Las Vegas.

The reality star got the party started at Blush Boutique Nightclub Friday night, and picked up on it today at Encore Beach Club at Encore Las Vegas.

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The first America's Next Top Model winner and My Fair Brady star, who separated from husband Christopher Knight in May, turned 29 today.

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DWTS pros Maksim Chmerskovskiy and Cheryl Burke, reality vixen Holly Madison, Vanilla Ice and Lil Jon were all part of the scene at Encore Beach Club at Encore Las Vegas on Monday as the hip club celebrated its first anniversary.

PHOTOS:  Stars Come Out For Encore Beach Club Anniversary Bash

Maksim and Cheryl were spotted dancing to Deadmaus5, the music phenom who performed a set, while Holly’s World star Holly Madison hung out with her  Playboy Playmate pal Lindsey Gayle.

Nobody fills out his swim trunks quite like Michael Phelps and he didn't let his fans down Saturday when he opened the 2011 season of Encore Beach Club at Encore Las Vegas.

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The 14-time Olympic gold medal winner led a champagne ceremony for a crowd that included Miss Nevada Sarah Chapman.

Hundreds of his mostly femme fans cheered when Phelps joined them in one of the club's three pools -- the guy can even dance in water!

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Phelps hopes to add to his medal count at the 2012 Olympic games in London.

PHOTOS: Michael Phelps Back In The Pool

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