The folks who put together the 'Cold Mountain' soundtrack (primarily T. Bone Burnett of 'O Brother' fame) have used Sacred Harp singers, giving the traditional singing style new exposure:
The music, also known as shape-note or fasola singing, has been waiting a long time for that attention. The style of singing, whose rudiments stretch back at least to Elizabethan England, flourished in Colonial New England and in its present form took deep root in the rural South, where it is still sung today in four-part harmony. But many of its practitioners â€” whose parents and grandparents and great-grandparents sang it in little churches and town squares throughout the South â€” fear it could die out. So they are waiting eagerly to see whether the use of Sacred Harp music on the movie's soundtrack, released on Dec. 16, could do for their music what the soundtrack for "O Brother, Where Art Thou?," the Coen brothers comedy, did for rural blues and bluegrass. (The "O Brother" album unexpectedly sold more than five million copies and won the album-of-the-year Grammy in 2002.)
It's an article worth reading, and likely a soundtrack worth picking up.*
But doesn't everyone's hymnals have shaped notes?!
* I highly recommend buying Tim O'Brien's CD 'Songs From the Mountain', which was put together before there was a 'Cold Mountain' movie. They should have just used this for the soundtrack.