Server Cloud Concept

I want to develop cloud server like as windows live or gmail.How can i develop and i want some of open source tools for develop this type to design concept.
Please suggestion me ,how to do it ?

If you are asking that question, is it worth going back a few steps and trying to make a functioning system before trying to take on the world? Either that, or look into using a solution that is already a cloud service and build your platform to make th e most of it?

There is owncloud, (open source)