At the 2015 Grammys, Beck performed "Heart Is A Drum" as a duet with Chris Martin.
(And, of course, Morning Phase won Album Of The Year. Prince presented Beck his award, which was obviously the highlight of Beck's evening.)
Reports from backstage after the show said Beck jammed on some songs with Chris Martin (and possibly Blue Ivy Carter). Kanye ranted about the ceremony afterwards, which brought Beck a ton of media attention (even more than winning an award did).
[people and bands
Bass: Justin Meldal-Johnsen
Drums: Joey Waronker
Guitar (Acoustic): Beck Hansen, Jason Falkner, Smokey Hormel
Other Band: AC/DC, Annie Lennox, Ariana Grande, Beyoncé Knowles, Common, Dwight Yoakam, Ed Sheeran, Electric Light Orchestra, Gwen Stefani, Hozier, John Legend, Juanes, Kanye West, Katy Perry, Lady Gaga, Madonna, Mary J. Blige, Miranda Lambert, Paul McCartney, Pharrell Williams, Rihanna, Sam Smith, Sia Furler, Tom Jones, Tony Bennett, Usher
Other Guest: Prince
Piano: Roger Joseph Manning Jr.
Vocals: Beck Hansen, Chris Martin
Vocals (Background): Jason Falkner, Roger Joseph Manning Jr.