how to integrate wordpress on multiple subdomain

Hi,
my wordpress blog is on news.
now i want to add multiple sub-domain for different categories. like for games news, science news, strange news, politics news.
i want to put all these categories in different sub domains.
and i want only a single admin login.
and also i want to show the posts of sub domains on my main domain.
that is a summary is displayed on my main domain and whenever someone click its gets redirect to that subdomain.
please help me out.
thanks
??