Redox is a Unix-like Operating System written in Rust, aiming to bring the innovations of Rust to a modern microkernel and full set of applications.
Redox is an attempt to make a complete, fully-functioning, general-purpose operating system with a focus on safety, freedom, reliability, correctness, and pragmatism.
Rust has enormous advantages, because for operating systems safety matters. A lot, actually.
Since operating systems are such an integrated part of computing, they are a very security critical component.
There have been numerous bugs and vulnerabilities in Linux, BSD, Glibc, Bash, X, etc. throughout time, simply due to the lack of memory and type safety. Rust does this right, by enforcing memory safety statically.