He got David Letterman to come out of retirement.
It turns out that Letterman was so bothered by missing out on joking about Trump running for president that he put together a Top Ten List and decided to go public to deliver it. As it happened, Steve Martin and Martin Short are touring together (perhaps in a "Martin and Martin" show) and were currently in San Antonio, Texas. Letterman flew down there, where they invited him onstage -- complete with his new beard -- to an enthusiastic reception.
There's some amusing chat up front, and then he gets into his Top Ten List at around the 3:45 mark. It's not the best he's done, but it's a pleasure to see,
Here's the 8-minute appearance.