Blogger Kiyoshi Saruwatari claims that Nintendo's upcoming Wii console runs on the open source Linux operating system. According to Saruwatari, who claims to be a Nintendo insider, the company reduced development costs by leveraging open source software and incorporating a Linux kernel into the Wii software platform. A wide variety of additional features like web browsing, video playback, file management, and emulation all run on Nintendo's custom Linux operating system, which uses a proprietary interface. Unlike the other specialized software components, the actual games will not run under the Linux platform, and can be played without booting Linux if the user holds down the "A" button while the Wii is starting up.
http://arstechnica.com/news.ars/post/20061009-7939.html