Der Brucer and I have seen Anyone Can Whistle, in Los Angeles. Not in a spectacular, first class production, but it's not a first class show. Still, it was enjoyable.
I would have loved to see the original production of Follies. On the other hand, we saw the London rewrite, which not everyone can claim. I'd also love to see a good live production of A Little Night Music, although we have the New York City Opera (or was it the Met) production on tape somewhere. Pacific Overtures we saw in London, a matinee the same day as Follies in fact. Company I saw in college, with a young Bob Westenberg in the lead. Merrily We Roll Along was another college production, original script, when I was living in Fullerton. Come to think of it, the only Sondheim I haven't seen in some form are Saturday Night, Do I Hear a Waltz, and Assassins, and the last we'll be seeing in June.
I really would like to see a good production of Lady in the Dark, but feminists today would be screaming about the ending, I'm sure.
I remember seeing Porgy and Bess on television when I was wee/spring/twig. Don't know how the Gershwin people let that screening slip by.
Set the way-back machine to 1936, Sherman, and load everybody in, because we're going to London to see Noel Coward and Gertrude Lawrence in Tonight at 8:30, all three nights worth!