Get ready for the smooth sounds of Michael Bublé and ... Reese Witherspoon? Yep, the two are pairing up for a duet on the Canadian crooner's next album. Fortunately we already know Witherspoon can sing, thanks to her role in Johnny Cash biopic Walk the Line, but one has to admit it's still an odd pairing. When Celebuzz heard about it, the gossip site was inspired to round up 11 other strange celebrity duets—and in the spirit of the season, four of them are Christmas songs. Click through for some of the highlights, or check out the complete list.