The greatest duet ever. Billy Preston (the 5th Beatle) and Syreeta Wright (Stevie Wonder's 1st Wife and owner of the purest voice I've  heard this side of Eva Cassidy) make history. John Legend and Mariah tried to duplicate this, and failed miserably. The song was recently played on an episode of "Glee", but once again, this one is best just left alone ot the two originals.