We're not sure Light nightclub at Bellagio needed a rehab, but its owners (who are also behind Jet, Stack, Fix, Bare, and Caramel) apparently thought it did. Thankfully, the simple rectangular layout and overwhelmingly positive energy remain, and efficient doormen and great resident deejays provide all the more reasons to keep loving it. The decor hints at opulence more than the previous incarnation (walls of Cristal flank the entry, strands of crystals drape from the ceiling, and floral motifs are etched into glass around the mezzanine). So does the drink menu: The table minimum has gone up to three bottles (that's over $1,200) on Saturday nights. Try booking Table 20 if a celeb hasn't nabbed it first: You'll have a great view of the entire club, yet you'll still be part of the action—that is, close enough to persuade a passerby to join you for a drink.

Open Thursdays through Sundays 10:30 pm to 4 am.

If you despise the Las Vegas nightclub machine (excessive cover charges, wristbands, and TSA-like mazes of velvet rope), this is a worthy alternative. Blush at the Wynn fills the void between big-box nightclub and lobby lounge, providing an intimate atmosphere with a live deejay on weekends. Seating doesn't require a minimum bar tab or bottle purchase, and there's no dress code. But with all these conveniences comes a noticeably different crowd, and it's an awkward mix at times: Guys just off the golf course mingle with suits in town for a conference, bachelorette parties, and couples ready to hit the sheets. The club lists a $30 cover charge on weekends, but our experience has shown this to be an uncommon practice. If you're in town on a Tuesday, stop by for Blush's popular industry night to experience weekend-like nightclub revelry with a more sophisticated crowd.

Open Tuesdays through Saturdays 9 pm to 4 am.

There is really only one word to describe Body English: sexy. More than any Vegas hotel (save for the Palms), the Hard Rock has always been known for its anything-goes atmosphere; the lack of inhibition carries into this two-story nightclub created by famed L.A. promoter Brent Bolthouse. Expect dirty dancing on the main floor, which is surrounded by mirrored black walls underneath ornate Baccarat crystal chandeliers. Some of the sexiest visitors to Vegas put Body English on their weekend hit list and they arrive ready to flirt, mingle, and find out if what happens in Vegas really stays in Vegas.

Open Wednesday, Friday, Saturday, and Sunday 10:30 am to 4 pm.

Standing on the outside pool deck of Cherry, sipping cocktails under the stars surrounded by beautiful people—is this L.A.? In a sense, it is. The sexy atmosphere is the creation of Rande Gerber, nightlife mogul and Mr. Cindy Crawford, and the crowd is mostly locals and SoCal visitors escaping the Strip's tiresome traffic. (The cab ride from the Strip to the Red Rock Resort will take about 30 minutes.) The entrance is a womblike tunnel that emerges into an oval-shaped room where metal, mirrors, and red leather are woven together: an interpretation of life inside, well, a cherry. Summertime, reserve a poolside cabana, outfitted with flat-screen TV, mini-fridge, and privacy curtains.

Open Wednesday, Friday, Saturday, and Sunday 10:30 pm to 4 am.

In an era when even airport bars have a signature cocktail, it's reassuring to know that the true art of mixology hasn't been lost. The Downtown Cocktail Room, a dimly lit joint with a hidden entrance well off the Strip, is a haunt for local artist types that nonetheless takes its drinks seriously. As your bartender playfully squabbles with the cocktail waitresses, he's running obscure ingredients through his head to make your drink. When we visited, we gave George the bartender a test: Make a gin-based cocktail that would convert an avid anti-gin type in our group. He passed with a fresh and fragrant cucumber-tinted concoction. We also recommend his Le CHAIse Sipper—a cocktail of Ketel One, elderflower liqueur, ruby red chai tea, cherry juice, and agave nectar. Served in a cognac snifter, the drink is as much about smell—a piece of sage and a cinnamon stick floated on top—as it is about taste.

Open Mondays through Fridays from 4 pm, Saturdays and Sundays from 7 pm.

A 30-year-old dive bar located behind a greasy spoon restaurant on the Strip? Now you're talkin'. Walk into the front door of the Peppermill Restaurant and turn left—yep, that's a sunken fire pit and black-light-lit, dark-as-night room full of red velvet couches. The Fireside Lounge is open 24 hours a day, seven days a week, and the vibe never changes no matter the hour. Fake foliage, electric candles, and fruit-topped tropical drinks never go out of style here. You're guaranteed to see all types of humanity, from the guy that got stuck in Vegas back in '72 to furtive couples who are married (but not to each other). Insiders know there are a few off-the-menu cocktails such as the Scorpion—a killer mix of two vodkas, two rums, two brandies, and OJ, served in a massive bowl.

Because there's no dance floor, Ghostbar attracts a slightly older clientele who like to step outside on the terrace for a cigar. But be careful: If you plan on heading up to this rooftop lounge at the 56-story Palms before heading to Rain nightclub, you may never actually make it. Designed in a retro-futuristic motif, it's famous for the window in the floor of the terrace that looks straight down over the Strip. On weekends, the crowd is shoulder-to-shoulder, so seats are hard to come by. This was the spot where Britney Spears decided to get married—so you know the drinks are strong.

Open nightly from 8 pm.

There was a time when the Hookah Lounge was known only to a privileged few, and even weekends saw empty velvet sofas. Now it's packed with the stiletto-and-halter-top set, but nothing can take away from the dark, mysterious ambience. The room feels like a scene from a Bond film, with people smoking hookahs as house music pulsates in the background. You'll get a choice of some 20 flavors of tobacco; there's also an exotic cocktail menu and a menu of mezes from the Mediterranean restaurant next door.

Open daily 5 pm to 1 am.

Frequently voted Best Gay Bar in Vegas, Krave is more accurately two venues: On weekdays it's a midsize lounge with a neighborhood-bar vibe; on Fridays and Saturdays the massive concert and nightclub space next door opens up, creating a megaclub that fits more than a thousand. Aerial acrobats take to the ropes while shirtless boys dance to club anthems and house music. Cirque du Soleil performers frequent Krave after their second show on weekends, as do groups of straight girls looking to dance without being groped. On Saturday nights the lounge area is converted to "Candy Bar," making it the prime place on the Strip where lesbians can go to drink, dance, and meet other girls.

At Luxor's Lax nightclub, it might take you 20 minutes to inch from the entrance to the back bar; but for Vegas weekenders thick crowds are precisely the draw. (It might also help that Christina Aguilera is a partner and has been known to drop in for cameo appearances, as have cast members from The Hills.) To rise above the fray, call ahead to the downstairs Noir Bar, a reservations-only adjunct accessible via elevator from the Lax entry foyer (702-262-4529). The long, brick-walled room feels like a members-only lounge, and the speakeasy vibe is enhanced by bartenders who have virtually every obscure ingredient at their disposal. Trustworthy friends recommended the Peanut Butter & Jelly Martini (with Hanger One raspberry vodka, Nocello walnut liqueur, Pallini Raspicello, peanut butter, rock candy syrup, and raspberries, all served in a peanut butter–rimmed martini glass). Those friends are not trustworthy anymore, but the drink has a loyal following. Hey, you're in Vegas—there's no accounting for taste.

Open Wednesdays through Saturdays 10 pm to 4 am.

Mix Lounge has become the Vegas version of the Empire State Building: Located on the 64th floor at the top of THEhotel at Mandalay Bay, it's known for having the best views in town: You can peer straight down the Strip's thick pastiche of neon lights from the street's southern tip. Even the restrooms have amazing vistas. Access to the lounge is free daily from 5 p.m. until 10 p.m., after which a $20 to $25 cover is charged.

Open Sundays through Tuesdays 5 pm to 2 am, Wednesdays and Thursdays 5 pm to 3 am, Fridays and Saturdays 5 pm to 4 am.

The Playboy Club and Moon nightclub occupy the top two floors of the Palms' Fantasy Tower. The Playboy Club marks the rebirth of Hef's old brand, and you'll have to pay a cover and wait in line up to 45 minutes after 10 p.m. to access the gambling/lounge area (the only gambling space in town to demand an entry)—where you'll find, yes, hot women in bunny suits dealing cards and delivering drinks. The decor is sexy-cheesy: neon Playboy signs, fireplaces. Those looking for a something more 21st-century head up the escalator to Moon, where the dance floor is framed by massive windows looking over the Strip and live projections on the ceiling. The demographic skews younger in Moon and older in Playboy, but there is a free flow of people between the two.

Playboy club open daily from 8 pm; Moon open Tuesdays, Thursdays, Fridays, Saturdays, and Sundays from 10:30 pm.

Once Vegas hotel owners realized that the nightclub set was either sleeping the day away or trying to wave down a cocktail waitress by the pool, they hit upon a business opportunity: the poolside club. So began Rehab, a daytime, poolside party at the Hard Rock Hotel that debuted in 2004. On Sunday afternoons, the hip and sexy spend the day soaking up sunshine, eating and drinking, and flirting with one another—all accompanied by a live deejay or hip-hop act. That scene still thrives, but today there are options almost every day of the week, and most of them allow for European (topless) sunbathing. Moorea Beach Club is separated by a wall from the massive beach complex at Mandalay Bay, with its third-story cabanas, beachside gaming, and sea of chaises. Moorea is the intimate meet-and-mingle option, where the crowd is mixed and the vibe laid-back. Bare at the Mirage feels like your rich Miami friend's backyard—it's small by Vegas standards, but dark planks of wood and overgrown trees make it feel secluded. There's an aboveground, glass-walled pool in the VIP area and tiered cabanas where topless sunbathers show off their, um, goods. Tao Beach at the Venetian is a mirror image of the eponymous nightclub—loud, fast-paced, and geared towards younger spring-break types. MGM's new Wet Republic is one of the largest European-style pools, and Venus at Caesars is favored by those looking for a more relaxed scene—though it's run by the folks at Pure nightclub, so expect things to heat up eventually.

These special pool areas are sometimes only open on weekends, so call ahead or check web sites. And always be among the first to arrive, or reserve a day bed or cabana, lest you find yourself sitting along the pool's edge or—worse—nowhere at all. Cabanas can set you back over $1,000, so call for pricing.

Lately known as the place where Britney passed out from "exhaustion" during New Year's 2006. Caesars Palace previously had no nightlife venue, but that's much changed since the opening of this 36,000-square-foot space co-owned by Celine Dion, Shaquille O'Neal, Andre Agassi, and Steffi Graf. The VIP Red Room is one of the hardest spots in Vegas to finagle your way into as A-list celebs set up camp for the night.

Open Tuesdays, Fridays, Saturdays, and Sundays from 10 pm.

Proof that style trumps size. There's no dance floor, so the tables do double duty as bottle service and platforms for female patrons who can't resist the urge. Although more of a dress code should be enforced to match the sexy, futuristic interior by designer Jeffrey Beers, don't let that stop you from dolling up—especially since the intimate size of the place makes it easy to meet people. And if you're tired of incessant hip-hop, you'll be delighted to know that the DJs favor deep, soulful house over trendy club hits (except for Sunday, which is, in fact, hip-hop night).

Open Thursdays through Mondays from 10 pm.

This branch of the New York hot spot inside the Venetian is an Asian restaurant, lounge, and nightclub. Unless you've reserved a table by purchasing bottle service, gaining entry to the club will be the challenge (or wait) of a lifetime, so make late dinner reservations (10 or 11 p.m.) and ask your server to pull aside the velvet rope. The nightclub upstairs is filled with dark, cavernlike spaces, a lounge area that feels like the Hearst Castle's living room, and a huge main room that resembles a warehouse with chandeliers. It's not uncommon to see lingerie-clad girls massaging one another on daybeds.

Open Thursdays through Saturdays 10 pm to 5 am.

Tryst's entire back wall is open to a small lake fed by a 90-foot waterfall, so clean air wafts in and cigarette smoke goes out. This alone makes it a winner, but the 20- and 30-somethings in their finest threads meandering through spaces like the red library room (compete with a stripper pole for flirty female guests) don't hurt either. If you order bottle service, reserve a table outside for better people-watching. The best are in the far corner just to the left of the waterfall—you'll be able to hear your date talk but still feel connected to the club's energy.