This past Saturday afternoon, Justin Vernon (Bon Iver) joined up with Annie Clark (St. Vincent) and old friend Brad Cook of Megafaun, just to throw together a band for that evening's Haiti benefit at Music Hall of Williamsburg. They named their supergroup Songer Singwriter. At the end of an already wonderful night that included performances and stand-up from the likes of Britt Daniel, Janeane Garofalo and Zach Galifianakis, they rolled out covers of Neil Young's "Harvest Moon," Tom Petty's "A Face In The Crowd," Annie Lennox's "Why," as well as an ear-splitting version of Dolly Parton's "Jolene." Vernon told us after the show that the Cook-fronted Petty cover was his favorite moment of the night, but we had to respectfully disagree: the way he and Clark traded verses on one of Young's very best is something we'll only forget if you hit us on the head a few times with a hammer. Please don't do that.