What Are Some Acoustic Songs You Would Like to See Ed Add to His Repertoire?

I always love how the encores often start with Eddie doing an acoustic number; he's covered the Beatles, Springsteen, Petty, Waits, and numerous other great artists. Are there any songs that he hasn't done yet that you'd love to hear him sing? Personally, I've always wanted him to do the Grateful Dead's quieter numbers ("Ripple," "Brokedown Palace," "Wharf Rat").