Actually, this could be a fun thread, depending on what obscure anecdotes people post. Even if they're not true, if they're part of theatrical lore, why not go for it?
Here's one: I saw the original production of "Chicago." The "sob sister" reporter was played by a man who eventually removed his wig, I think during the curtain calls, so the audience members could see he was male. The Playbill listed the actor's name only by his initials. However, his understudy had a female name. I never figured out whether a female understudied the role, or whether her name was there solely to confuse people. Maybe someone with more obscure knowledge than I have has information on this.
Audrey, the Phantom Phanatic, who nonetheless would rather be Jean Valjean, who knew how to make lemonade out of lemons.