Robin Williams was also one of the filmgoers

Many of the films being shown are dark, reflecting works that deal with substantial real-life issues.

The more sombre mood was noticeable when the festival kicked off with its high profile opening night film The Laramie Project, a chronicle of the real-life gay bashing of student Matthew Shephard in Wyoming in 1998.

The festival has also commemorated the US attacks with a special programme of films.

But even though the festival may seem a little less boisterous than it has in the past, it is still a huge magnet for stars.

This week Park City has been visited by Mariah Carey, Jennifer Aniston, Brad Pitt, Matt Damon, Christina Ricci. Andy Garcia, James Coburn and Robin Williams.

Denise Richards arrived for the premi�re of the film Empire

Jodie Foster and Nicole Kidman are also scheduled to make an appearance.

For many stars the attraction of the festival is that it celebrates work that presents creative opportunities that can be far more satisfying than that offered by typical Hollywood fare.

A case in point is this year's festival entry Narc, a well-received crime drama in the same vein as Quentin Tarantino's violent classic Reservoir Dogs.

The film, starring Ray Liotta and Jason Patric, was made despite a low budget - at times the production almost closed down because of financial difficulties.

Some actors come to Sundance with films they hope will help re-make their image or boost their careers.

Robert Redford: Founded the festival

Mariah Carey had a disastrous entry into the movie world last year with Glitter, but in the entertaining mafia crime drama Wisegirls she has fared much better.

Carey, who plays a no-nonsense New York waitress, said: "I just felt that the script was interesting, it's a totally different point of view on the mafia world, and it's about empowering women."

Carey's performance in Wisegirls was no disgrace and she leaves Sundance with some credibility as an actress.

Jennifer Aniston also emerges from Sundance with an enhanced image.

In the film The Good Girl she plays a conflicted woman who enters a nightmarish world when she strays from her marriage.

Joshua Jackson was The Laramie Project, which premi�red

"I was frustrated with the umpteenth romantic comedy that had come across my desk, you don't want to get pigeonholed," she said.

And her performance has proved she can do more than play just cutesy and nice.

Although Sundance is without doubt an international affair, the British presence at the festival has been less pronounced than in previous years.

The most controversial offering has been the already well-publicised Bloody Sunday, which had its world premi�re at Sundance.

Frivolity

Speaking at Sundance, director Paul Greengrass said: "One of the lessons of Bloody Sunday is what happens if you get it wrong in a war against terrorism, I think there's a lesson there for this country".

The film was greeted with strong applause at its Sundance premi�re, but while many praised it for powerful content, some agreed with critics who said it lacked balance.

Although serious films have been in vogue this year there has still been some frivolity up on the screen.

Britney Baby - One More Time, a road move and satire starring Britney Spears impersonator Robert Stephens has drawn a few laughs. He sees the film as "a social commentary about the status of celebrity".

Obsessed

It hasn't yet found a buyer, but that's true for most of the films that are being screened at the festival. But even with a depressed economy there has been some dealmaking at Sundance.

One of the biggest Sundance sales triumphs has been the romantic comedy, Tadpole, which tells the story of a precocious teen who's obsessed with older women.

The film stars Sigourney Weaver, but it was shot in 14 days on digital video at an estimated cost of $150,000 (�104,000).

It was sold this week at Sundance in a deal which is reported to have exceeded $5m (�3.4m).

It's a tale of Sundance success that will, sadly, elude most of the films being shown here which will never enjoy a release in cinemas.

Sundance may be brimming with bold, daring talent but that does not change the sobering reality that when it comes to distribution the market for independent film still remains very limited.