R.E.M.’s Michael Stipe made a pair of high-profile public appearances last night, first popping up on “The Colbert Report.” to sing the Christmas carol “Good King Wenceslas” with Stephen Colbert and Mandy Patinkin, then joining Coldplay’s Chris Martin to perform “Losing My Religion” at 12-12-12: The Concert for Sandy Relief.

Paul McCartney closed out Wednesday night’s marathon 12-12-12: The Concert for Sandy Relief and had a few special guests up his sleeve: the surviving members of Nirvana, who reunited to back McCartney not on one of Kurt Cobain’s songs or a Beatles classic, but, rather, a sludgy new rocker called “Cut Me Some Slack.”

We interrupt our regular programming to present what promises to be a historic musical event, 12-12-12: The Concert for Sandy Relief, featuring performances tonight from The Rolling Stones, The Who, Bruce Springsteen and, reportedly Paul McCartney fronting the surviving members of Nirvana.