More than a hundred new films unspool every January at the Sundance Film Festival, many of them never to be seen again. So what is it that draws stars, studio moguls and journalists to these snowbound screenings year after year? It's the hope that they'll see something new and groundbreaking, fresh and original, something that in turn will wow moviegoers everywhere else.

After all, Sundance has a long history of turning obscure filmmakers into showbiz Cinderellas, of serving as a farm team scouting indie filmmakers who can play in the Hollywood big leagues -- or, if you prefer, simply introducing the world to great artists who might not otherwise have seen the light of day.

Here are 15 of the biggest breakout hits from Sundance, films that either became huge box office smashes or were enormously influential (or both), movies that proved that the road to Hollywood success often begins in Utah.