"Magnolia" is a beautiful song by JJ Cale, and can be found on his 1971 album, Naturally. He is mostly famous for having written a couple of Eric Clapton's biggest hits in the '70s ("After Midnight" and "Cocaine"), but he also had a pretty decent career as an artist himself.
Beck covered this for the first time on August 18 2002, in Washington, DC. He played it alone on the piano.
He played it again a few months later, at the concert that was being filmed for the PBS TV show, Austin City Limits. This time he did it solo on acoustic guitar, "just like I'm sitting on my bed." Very beautiful and tender performance.
On March 31 2003 Beck played "Magnolia" one more time, again on acoustic guitar.