Not on Broadway, but Anthony Warlow's last high A in "Alive" on the complete concept recording of Jekyll and Hyde. Any note he sings makes me melt, but that one especially is worth a listen.
I agree with g.d.e.l.g.i. Neeley's "myyyy" and "whyyy". I don't know that he ever did it on Broadway..but there's the movie and what, 2000? other times all over the country.
Actually, he did do it on Broadway... in the "Same Role for 30 Years" thread, I mentioned that he played a Reporter/Leper and understudied the part of Jesus in the original O'Horgan production. He was actually O'Horgan's first choice for the role (paired with Ben Vereen as Judas), but as Ted describes it, Stigwood wanted Jeff Fenholt and Carl Anderson from the tour, and the authors were splits, so O'Horgan called them both and said, "I don't know what the compromise is, but I'll get back to you." It wound up being Fenholt/Vereen, with Neeley getting a chorus part and understudy slot to make up for it.
Anderson, of course, later began doing four performances a week when Vereen developed polyps on his throat, and he and Ted took the show out on national tour, starting with an outdoor run at the Universal Studios Amphitheatre. During the tour, they were offered screen tests for the film as further compensation for both losing at Broadway (merely a formality, as apparently the director originally wanted Ian Gillan and Murray Head from the album, and then Fenholt when Gillan was unavailable), and history was made when they blew the screen tests out of the water.