Bruce Springsteen stunned fans at Lisbon, Portugal's Rock In Riot festival yesterday when he joined the Rolling Stones for a duet on "Tumbling Dice." They played the same song in 2012 in Newark, New Jersey, at a show broadcast live on Pay-Per-View.
So we have a question for you: What is the greatest duet of all time? Feel free to go for a cheeseball classic like Sonny and Cher's "I Got You Babe" and Elton John and Kiki Dee's "Don't Go Breaking My Heart," an MTV-era favorite like Mick Jagger and David Bowie's "Dancing in the Street" and Steve Nicks and Tom Petty's "Stop Draggin' My Heart Around" or a 1990s R&B jam like "The Boy Is Mine" by Brandy and Monica. Vote for whatever duet you want, but please use vote once and only for a single song.