It means that I use my computer on a home adsl connection as a ssh tunnel
and that I let some friends use it as well but I don't want them to abuse.
What we are doing is connecting to the ssh server with some ssh client, it
creates a socks proxy on our local computers, we configure our programs to
connect to the local proxy and everything is forwarded trough the ssh
tunnel.
I mean, I don't know if there's another way to do it without having to login
Yeah, utmp sounds useful for this.