What’s better than a musical powerhouse taking the stage before thousands of screaming fans? Two musical powerhouses taking the stage before thousands of screaming fans. It is all too rare an occurrence that singers join forces for an epic concert experience for the fans that adore them. But the union of Mr. and Mrs. Carter “On the Run” together has given us renewed hope that there are years of superstar-duo tours in our future. Here are the musical duets we would love to see.