JacobAnd out of left field, it's Nintendo! Never saw this one coming, did you?
The folks at OSNews have unearthed an interesting, not well-known discovery: Nintendo has released the "Nintendo ES" operating system, and not only that, but under an entirely free and open-source license.
The OS is written in C++, runs EMCAScript (JavaScript), uses Cairo for rendering, and as of recently, can run Squeak, a Smalltalk programming language implementation.
The official website includes screenshots, news, and some specifications, although it is all in Japanese. Google can come in handy.
The following screenshot is Squeak running on N-ES, virtualized with QEMU:
This project from Nintendo R&D is in very early development, but it could have a great amount of potential. No specifics are available as to what it can be used for or why it even exists, but we can only speculate. A Wii development kit? Unlikely, but possible.
"We propose an extensible component operating system architecture in which an operating system kernel uses reflection to process C++ pure virtual function based system calls and upcalls to provide a unified programming environment for application, server, and kernel development. We found that we could even develop file subsystems and a TCP/IP protocol stack on an existing operating system based on this architecture."
