The Secret Sisters is a new Jack White/T Bone Burnett discovery who have just released their first record, The Secret Sisters. Maggie loves them! They do a very shreddy electric guitar version of Johnny Cash's "Big River" with Jack White, but it's mostly old school Patsy Cline-esque country folk tunes.
"Tennessee Me" (written by them):
"Do You Love An Apple" (old Irish folk song):
Here are some more songs they did for a Rolling Stone magazine session.