"Today, you will learn how to install Ubuntu Gutsy (as a second operating system) on your PlayStation 3 gaming console. For those of you who think for a second (and who are scared) that this will replace their PS3 operating system, well you guys are wrong, because this will NOT erase your PlayStation 3 native operating system (called XMB) and it will run as an alternative OS on your PS3 console. Ready? Are you excited? Let's go!"
http://news.softpedia.com/news/Ubuntu-7-10-on-PS3-73272.shtml