Telnet - not that useful but you can sometimes get into email accounts that are annonymous... lets begin!
hold down the windows key + R and type in cmd. now type in nslookup, you see that difficult server, WRITE THAT DOWN!!! now you exit that and open up CMD again. this time type in telnet then the server you wrote down 110 like this

telnet comcast-ill.net 119 or something similar.

it doesnt always work, but them type in HELLO if it works..
then type in send data = and type a message and it will send it to your internet providers.