The tricky part is getting connected to that detached shell. I first encountered detached shells while tinkering with Chicago Boss (which I highly recommend even though it's a bit experimental), but I suppose I should first show you how to start a detached shell though, in case you are wondering. Of course, you would probably want to start an app or something from the command line as well (a detached shell is otherwise rather useless), but here is a barebones command:
erl -sname servernode -setcookie myR4nd0m_c00k!3 -detached
Great, so we've got this detached node. Now how do we connect to it? In the following command, you can put pretty much whatever you want for the sname argument as long as it is unique. The remsh command is the interesting part; the first chunk of the remote shell info contains the registered name of the node (this is why we use the sname argument), and the hostname is somewhat dependent on your setup. Your box may be configured to accept Erlang connections via a fully-qualified hostname. However, the default behavior seems to be looking for just the short hostname, as given by hostname -s.
erl -sname node1 -remsh servernode@hostname -setcookie myR4nd0m_c00k!3