I'm the Internet Owner!!!

Hi, i have a very rare problem, i have instaled windows 2003 server, IIS, VS.NET, and some ASP.NET pages running on my computer. Now, sometimes when i looking something on internet and i type a wrong Internet Address, IE opens my own page.... For example if i write "http://web.msn.com/" (I believe that it doesn't exist, is it?) it opens a web page served on my machine and displays on the address bar the address: "http://web.msn.com/login.aspx".... of course with any other page occurs the same (ie: ThisIsAnInvalidPage.com)....

What's happening??? :sick:

Thanks,
Diego