I read a post about Online Operating System (OOS) at lifehack.org which will render choice for Desktop Operating Systems to anything, very soon.
The OOS is referred as Firefox OS because all the web applications run with-in Firefox. There is almost every desktop application that one needs for general needs from Office suite to File Management and HDD plus backup system, Calendar, Email and Photo Softwares.
I found that I have already been using all of them – not to miss any one :D.
Of course, OOS isn’t feature rich nor it is flexible for running heavy end development applications but it is evolving and evolving with power!