So I watched Moana a couple of weeks ago, and I loved just about everything about it, from the musical numbers ("Shiny" is my favorite), the overall coming-of-age story of Moana, the visuals, and the overarching theme. I like that it's representative of an underrepresented culture (Polynesia) and that it incorporates that culture's mythology. Maui is a demigod responsible for much of the state of the world. He's got a big magical fishhook. And he's got tattoos.
Tattoos that move.
Mini Maui acts as Maui's voice of reason and conscience, and in film and animation, it's something new to see. It lets us peek into the character's mind via something we see on his body.
In comics, though, it's a device that's been around since the Yellow Kid showed up in 1895. In lieu of actual speech balloons, the Yellow Kid's dialogue would appear on his shirt.
The effect is different, simultaneously both more jarring and more subtle than in film. Where the animators, the character, and the audience have to acknowledge that Maui's tattoos move, with the Yellow Kid, it's just a thing that happens. It's not mentioned and is just a part of the entire experience.
Strangely, the only writer I've seen play off of this type of device is Alan Moore, and twice. Girl One from Moore, Gene Ha, and Zander Cannon's Top 10, one of the best, most well-written, and most well-drawn short series of all time in any medium, is naked except for pigments on her skin. These pigments change into various configurations reflecting her mood.
It's subtle most of the time, but sometimes you get something like comic book sound effects when she's getting ready for action.
The most famous play off of this (until Moana anyway) is Rorschach from Moore and Dave Gibbons' Watchmen, whose face changes with each panel.
It seems random, but then you get something like these two panels from the first issue and the last.
The (terrible) Watchmen movie translated this into live action, but because of the constant shifting and movement in film, it does call more attention to itself.
Are there any other examples of a person's costume or body elements changing to reflect their mood in the story?