Cross-genre pairings are nothing new in country music: Willie Nelson has lit up the charts with duet partners ranging from Julio Iglesias to Snoop Dogg. Johnny Cash once collaborated with members of Nirvana and Soundgarden. And CMT has made a whole show, Crossroads, out of rock-country mashups. But this year has seen more than its share of head-scratching duets — some that resulted in awe-inspiring, unique music, and others that genre-crashed and burned. Here are the 10 collaborations that surprised us most in 2014.