Swedish radio show Morgonpasset is having some of the artists who come to sing live perform Christmas songs and they've got the songs linked to on their site for you to listen to. If you like the idea of Darin singing "Oh Holy Night," Danny singing "The Christmas Song," Sibel singing "What Child Is This," or Amanda Jenssen and Erik Hassle singing original Christmas songs--all in acoustic, live, and usually abbreviated versions--go here.
Also on the Swedish music front, I recommend checking out the Idol medley from the Idol finale on Dirrrty Pop and Robyn performing at the Nobel ceremony on Oswalds Popcorn.