I wrote a web server to store markdown documents with links between them, a sort of 'zettelkasten'. Now I've made it into a tauri app that runs on my phone, web server and all, and can sync with the main server in the cloud. Documents everywhere! Front end is in elm and not rust tho.
I've made a few other projects in rust, did a audio dsp thing that is a delay with web controls, made a blinky sketch for the rp2040.
Rust is cool because you can write pretty high level code in it, with lots of libraries to help out, or you can write bare metal code with no OS for embedded.