The Grammys, as the Recording Academy likes to remind us, are “music’s biggest night.” They’re also an unparalleled opportunity for a varied group of artists across genres—from country to soul to rap—to convene under one roof for an evening. With so much distinctive talent in one place, it’s become a tradition for the show’s producers to dream up the most unexpected medleys and mashups.

Sometimes, these collaborations are a thrill to watch. Other times, they leave viewers scratching their heads. In preparation for Sunday night’s ceremony, here’s a roundup of 10 of the most memorable, from Eminem and Elton John’s seminal duet to that time Gwyneth Paltrow joined CeeLo Green onstage, accompanied by a gaggle of Muppets.

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Write to Raisa Bruner at raisa.bruner@time.com.

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