Confused? Just read on...
Let's start with the basics. It's well known that Alison Krauss sang on several tracks for the soundtrack to O Brother, Where Art Thou?, so let's start there.
We'll take a random non-Nashvillian like Ani Difranco. This is easy!
How about Janis Joplin? Seems impossible to make the connection, but it's not! Janis popularized "Me & Bobby McGhee," by Kris Kristofferson. Alison sang on Kris Kristofferson's song, "Why Me" on The Austin Sessions. Again, only two degrees.
Or how about Jeffrey Foucault? Now I'm just picking random names. But Jeffrey Foucault made an album with Kris Delmhorst called Redbird. Kris spent some time at the beginning of her career touring with Dar Williams, and Dar had Alison Krauss singing with her on "The One Who Knows" from her Beauty of the Rain CD. Three degrees! See how this can be a fun game?
It doesn't stop with music either. Take Keanu Reeves, for example. Keanu was in Speed and other missable films with Sandra Bullock. Sandra starred in the film adaptation of Divine Secrets of the Ya-Ya Sisterhood, the soundtrack of which Alison Krauss produced. Again, only two degrees.
So ... can we trace Kevin Bacon back to Alison Krauss? Naturally, it's only one degree of separation. Both Alison and Kevin appear on the album Dog Train a "read and sing-along children's book."