David Letterman and Paul Shaffer at 'SNL50: The Anniversary Special.' Dimitrios Kambouris/Getty Images Share on Facebook Share on X Google Preferred Share to Flipboard Show additional share options Share on LinkedIn Share on Pinterest Share on Reddit Share on Tumblr Share on Whats App Send an Email Print the Article Post a Comment David Letterman has signed on to executive produce Say Hello to Our Good Friend Paul Shaffer, an upcoming feature documentary about his longtime sidekick and Late Show bandleader. "Paul Shaffer is a show business friend who became a real friend.