In the 1990s, it was pretty unusual to hear songs that fuse distantly related musical genres together.  But the new millennium has introduced indie pop to hip-hop, R&B to alternative rock, American folk to dance music, and so on.  Even though genre fusions are the norm today, here are a few songs that made us take a double listen and wonder, “What the … ?!”

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Jay-Z and Linkin Park “Numb/Encore”

Mary J. Blige and U2 “One”

Alicia Keys and Adam Levine “Wild Horses”

Kanye West and Bon Iver “Lost In The World”

Lil Wayne and Mike Posner “Bow Chicka Wow Wow”

Lupe Fiasco, Eric Turner and Sway “Break The Chain”

Nelly and Tim McGraw “Over And Over”

Lil Mama and Avril Lavigne “Girlfriend”

Nicki Minaj and Pearl Future “Look At Me”

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