Now google going to open 'Google Chrome OS' by name. Google said that it will be release Middle of 2010. It is mainly for notebook computer. It have a few resource for that user can do any work very easily and don't need extra time. it uses Linux karnal for virus, mallware, Trojan. For details see below link
http://googlesystem.blogspot.com/2009/07/google-chrome-operating-system.html
Source: http://googlesystem.blogspot.com/2009/07/google-chrome-operating-system.html