The entire point of the 10th Anniversary Concert, which didn't have a principal cast member who wasn't a Broadway and/or West End luminary and/or have a major role in the show at some point including Colm Wilkinson, Philip Quast, Michael Ball, Lea Salonga, Ruthie Henshall, Michael Maguire, and Judy Kuhn.
The 25th Anniversary Concert followed suit; even Nick Jonas, more famous as a pop singer, had at one point played Gavroche on Broadway.
"Do You Hear The People Sing?" has also been used in connection with the Occupy Movement and other protest movements.
Romance on the Set: Actors Jason Forbach and Joseph Spieldenner met while playing Feuilly and Grantaire on the 25th anniversary US tour. Forbach soon took over as Enjolras, and the two played the famously Ho Yay-tastic pair until the tour ended in 2013, and got engaged at the end of that year.
Star-Making Role: This show made Michael Ball and Frances Ruffelle household names, and turned Rebecca Caine into a darling of the theatre world.
Tough Act to Follow: How do you ensure that this trope never applies to you? By writing a musical so good, so famous, and so beloved that its mere existence allows you to write whatever else you damn well please. This is that musical. (In Schonberg and Boublil's case, "whatever else you damn well please" was Miss Saigon, a critical and popular smash hit still known and beloved by most musical theatre fans. Go figure.)
Adaptation Overdosed: Over 60 movies, a musical, at least 5 different stage plays, about a dozen audiobooks, three comic books (one of them with the Duck family!), a spectacle son et lumière and two computer games (a point-and-click-adventure of the same name and the extremely weird beat-'em-up Arm Joe).
Adaptation Sequence: The '52 movie calls itself a remake of the '35 movie. Then they made a radio play out of the '52 movie.
Cast the Expert: According to the DVD booklet, the extras who played the convicts in the 1935 movie were recruited from a nearby prison.
Especially with first names of characters that never get one in the novel.
One fanfic writer started calling Enjolras "Marcelin" and this has become the most often used first name for him.
Javert is often said to simply not having been given a first name. A popular joke also is that his first name is "Inspector".
Characters misremembering Valjean's name will always think he's called "Jacques Valjacques".
The novel mentions that Javert's mother is a fortune teller; in fanon, she (and thus also Javert) is Roma.
Actually, it says Javert had une inexprimable haine pour cette race de bohèmes dont il était ("an inexplicable hatred for that race of bohèmes of which he was one"). Bohèmes could be "bohemians", as in tramps/vagabonds, but really bohemiens would be better for that purpose; bohèmes almost certainly means "gypsies."
Susan Kay's novel Phantom (which as the title would suggest is a The Phantom of the Opera spin-off giving the character a back story as well as a first-person narrative of events) includes a minor character named Javert, who runs a freak show carnival Erik temporarily joins as a youth.