Whenever you chat with any of your friend via yahoo messenger ,ask him to send you any file it may be of any format(jpg,gif,txt,doc,docx)
while your friend send you the file.Immediately open command prompt
As command prompt will open,now type netstat
It will return the list of all connection made with your computer
Local address will show you the ip address of your computer and foreign address is the address of computer with which connection of your computer has made.
Local address will be of this form
127.0.0.1:44343
here 44343 corresponds to port no
now out of all these check where port no 80 comes ,if you find the port no 80 then the corresponding foreign address will be of your friend's IP address
