Jay-Z and Kanye West

On Aug. 8, 2011, Kanye West and Jay-Z released their garish, 16-song (assuming you get the deluxe edition) collaborative album Watch the Throne, capping off a prolific partnership that the rappers have enjoyed ever since Kanye produced “This Can’t Be Life” on Jay-Z’s 2000 album The Dynasty: Roc la Familia. Kanye quickly became known for sampling classic R&B and soul songs — like Bobby “Blue” Bland’s 1974 hit “Ain’t No Love in the Heart of the City,” over which he layered Jay-Z’s vocals to create the similarly titled “Heart of the City (Ain’t No Love)” on 2001′s The Blueprint. All in all, the rappers have worked together on more than 20 projects. Watch the Throne may be their most ambitious endeavor, but it probably won’t be their last.
Ella Fitzgerald and Louis Armstrong

Both jazz giants in their own right, the collaboration between Ella Fitzgerald and Louis Armstrong was, predictably, the stuff of legend. After dabbling with informal recordings years earlier, Fitzgerald and Armstrong released their first official album of duets, Ella and Louis, in 1956. Her sweet, pitch-perfect singing blended effortlessly with Armstrong’s deeper, raspier vocals. One year later, they followed up their debut effort with Ella and Louis Again, which saw the performers sing solos, and in 1958, their third and final album, Porgy and Bess, was released. The latter, a compilation of songs from the Gershwin opera of the same name, became their most famous collaboration and was inducted into the Grammy Hall of Fame in 2001.

























