There's quite a lot of UI elements in Serenity and they all help paint a detailed picture of this fantasy world the movie is set in. There's everything from cockpit interfaces, holograms to communication devices.
Strangely, one thing that really stood out for me was actually the gravestones, which displayed holograms of the person deceased. It's quite a cool idea and one that I haven't come across before. It reminded me of something I read about several years ago, where people in Japan were putting QR codes on tombstones. Although this may sound a bit eerie, in this instance it is done very elegantly and quite tastefully.
The thing I liked most about Serenity though, is how well packaged it is. Everything from the set design, costume design to the UI elements were created with a common thread. The design of the UI elements and the movie itself is also very stylised and this certainly helped. Because of this, I was able to experience and quickly understand what this world was all about.
The design style itself is a little blocky, using thicker frames and bold lines, and could reflect the era that the film was made (2005). Nowadays, for movies designed for a futuristic look, the approach leans towards very thin looking interfaces elements. But I like it, it suits the stylised fantasy world, and makes me nostalgic for late 80s and early 90s designs.
Trivia: One odd thing I noticed was the abundance of chinese characters scattered throughout the scenes. After a bit of digging, this was explained in the back story, where as a result of China and the United States being the two superpowers that expanded into space, they became the two dominating cultures.
Worth checking out the movie if you're into sci-fi.