It's a Saturday night in Atlanta. Some 800 well-dressed, middle-aged adults are sipping cocktails, listening to jazz . . . and playing Candy Land or Twister.

Welcome to "the new face of nightlife," courtesy of three 30-something guys who realized they were too old to go out clubbing every weekend, but not old enough for reruns of The Golden Girls.

"We didn't go into this saying, 'Let's create a new business that will change the way people think about Saturday night,'" recalls Imari Harvard, CEO of Timeless Entertainment Concepts. "My wife and I just wanted to put together an event where folks could come out for some nostalgic games, cocktails and conversation."

The 80 people who gathered at an upscale pool hall in 2005 had so much fun playing board games and acting like kids that Harvard decided to repeat the event the following month. This time 150 people showed up, and Play Date Atlanta was born. Along with business partners Ryan Hill and Ron Gaither, Harvard has used a licensing model to grow the concept into Play Date U.S., expanding into four cities and projecting$250,000 in sales this year.

Hill believes the appeal is simple.

"After you get out of your 20s and you have more responsibility," he says, "you find yourself going, 'Why was I in such a rush to grow up?' "

Almost by accident, Timeless Entertainment Concepts tapped into a timeless truth: Nostalgia sells.

"It's about trying to go back to a time when things were different," says David Sprott, an associate professor of marketing at Washington State University and the author of several studies on the topic. "When things are uncertain in the present time, looking backward is a comforting thing for people to do."

From Juno's hamburger phone to Detroit's muscle cars, signs of the nostalgia trend are everywhere. Bowling alleys are glam again, roller rinks are attracting a new generation, and even drive-in movie theaters have halted their long slide toward oblivion. Young professionals are playing in kickball and Wiffle ball leagues, then going out to order drinks like the Harvey Wallbanger that were last popular in their grandparents' day.

And board games? The trio behind Play Date may have stumbled upon their successful business, but The Intelligence Group, a New York City-based market research firm, has since come up with hard data showing that progressive 14- to 34-year-olds known as "trendsetters" prefer board games to video games by a margin of 60 percent to 40 percent. Small wonder that in February a company named Winning Moves re-introduced '50s favorites Parcheesi and Careers--complete with their original packaging.

Of course, this love for the old isn't entirely new. Anyone who's ordered biscuits and apple butter at a Cracker Barrel restaurant knows that people seem to love walls cluttered with nostalgic signs and advertisements.

Still, two things seem remarkable about the current craze for nostalgia. First, it's likely to get even bigger as 78 million baby boomers with $2.5 trillion in spending power grow older and more wistful for the "golden days" of their youth. If consumers look back most fondly on their early 20s, as some research suggests, then aging boomers should drive a renaissance of all things 1960s-related.

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Even more noteworthy is this: Younger people seem to be just as nostalgic. Sprott found that his research participants responded to nostalgic advertising themes even though their average age was only 21. And those folks who turn out for a Play Date evening of Chutes and Ladders? They tend to be in their peak earning years, not their golden years.

Still, nostalgia does seem to work a little differently for Gen X and Gen Y than it does for their parents and grandparents. The gosh-darned earnestness of Cracker Barrel might not have much appeal for younger consumers, who tend to be more ironic in their outlook.

"There's a certain smile factor," says Dan Adamson, a partner and creative director at Farm Boy Co-op & Feed Co. "The audience is in on the joke."

The "joke" for Adamson and his business partner, Brian Goldenman, is a $2 million company built on nostalgia for the American farm. Under the Farm Boy and Farm Girl labels, the company sells T-shirts, caps and other clothing that celebrate farm life with a wink and a nudge. "What do I eat first--the chicken or the egg?" asks one T-shirt, while a ball cap proclaims "Livestock Jock."

Goldenman says the brand is hot with the 13- to 28-year-old demographic because, "People romanticize farming as a simpler way of life--sort of an 'unplugged' lifestyle. Everyone at some point kind of wishes for that."

Still, Adamson says they are careful not to treat their younger customers like they are "kind of backwoods or country store. We've made farming a little sexy. Not crude, but a little bit sexy."

For Farm Boy, as for other companies, "hip nostalgia" seems to be working. And there's nothing old-fashioned about that.

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