Steve Morse is my favorite guitarist, and I've also long been a fan of the band Kansas and guitarist/keyboardist/songwriter Kerry Livgren. Morse replaced Livgren on guitar when Kansas reformed in the later 1980s.
Kansas put out a special live DVD a few years ago, and both Morse and Livgren put in cameo appearances. But perhaps even better than that, the soundcheck before the concert featured a version of "Down the Road," an early Kansas song, with Steve Morse and Kerry Livgren playing guitar.
It's kind of special.