4. "FourFiveSeconds" (with Paul McCartney, Kanye West) (2015)
In the Eighties, Paul McCartney introduced himself to a whole new generation of fans by duetting with Michael Jackson on "Say Say Say." He wouldn't pull another cross-generational stunt like that with any real success until 2015 when he found himself collaborating with Rihanna and Kanye West on "FourFiveSeconds." Kanye spearheaded the unlikely project since he was working with Rihanna on her new album Anti and had developed a friendship with McCartney, teaming up with him on the 2014 track "Only One." Built around Paul's acoustic guitar lick, "FourFiveSeconds" is unlike anything in the catalogs of either Rihanna or Macca. It gave the former Beatle his first Top Five hit in 31 years. He continues to play it at all of his solo shows.