When Fox Searchlight acquired "Once" at Sundance, it bought a film that came equipped with its own marketing campaign. The word-of-mouth indie hit plays out like a live-action mix-CD, a carefully curated collection of music from one lover to another — the music often saying more or as much as any dialogue can.

Glen Hansard and Marketa Irglova are the ones communicating via melody, and the two have spent much of 2007 taking their show on the road as Swell Season. Live, the chemistry between the musicians-turned-actors is undeniable.

The songs of "Once" begin delicately and innocently. But most have a tendency to build to something more brutish, as every somber piano line and sorrowful violin melody in the background serve to document the anxieties of a relationship.

The visible tension in the duo's performances is why the studio staged 27 movie screenings/concerts in more than 15 cities. But those live dates took on added importance this year.

About three months ago, the Academy of Motion Picture Arts and Sciences banned the mailing of CDs of potential music contenders to voters. The goal was to ensure that nominated songs are ones that are integral to the film and are heard within the context of the film.

So what's a studio marketing team to do? Offer the music live.

Fox Searchlight, for instance, has staged intimate "Once" events for the Hollywood Foreign Press Association, the Screen Actors Guild and the Tribeca Film Festival, among others.

"By seeing a live performance, an audience is bonded toward the musicians who are working so hard in front of them. It adds another layer to the experience," said Nancy Utley, chief operating officer of Fox Searchlight, who also sees that bonding as a box-office and awards-positioning tool.

In early November, Paramount Vantage hosted a screening of "Into the Wild" paired with a mini-concert on the studio lot from Eddie Vedder, who wrote several new songs for the film, and later in the month singer-songwriter Sondre Lerche played a pair of dates at the Troubadour to showcase the music he wrote for Touchstone's "Dan in Real Life."

Columbia Pictures had a Dec. 3 date scheduled at the Roxy with John C. Reilly to highlight the music from "Walk Hard: The Dewey Cox Story." Even films without original music got into the action: My Morning Jacket, Yo La Tengo and the Roots were among the acts that performed at a New York charity concert in honor of the Weinstein Co.'s Bob Dylan-inspired "I'm Not There."

It's all a nice change of pace from the standard screening and Q&A format. Music fans — at least those lucky enough to score invites to these shows — get the opportunity to see an artist of Vedder's stature in a rare intimate setting. But maintaining that exclusive feel isn't easy.

"I think it has to be done sparingly," said Randy Spendlove, Paramount's president of motion picture music. "It's a wonderful opportunity to see and feel the music ... but if there gets to be too many, it's no longer special; it lessens the impact."

And diminishes, perhaps, the advantage come Oscar season.

"It's an advantage in a sense that we are making music that's important to the film," Spendlove said. "Over anything, the music is part of the story. You'd be able to tell if it was fake, like if someone was glomming onto a superstar to market a film."