title: On localhost, how do I pick a free port number?
body: <p>I'm trying to play with inter-process communication and since I could not figure out how to use named pipes under Windows I thought I'll use network sockets. Everything happens locally. The server is able to launch slaves in a separate process and listens on some port. The slaves do their work and submit the result to the master. How do I figure out which port is available? I assume I cannot listen on port 80 or 21?</p>
  <p>I'm using Python, if that cuts the choices down.</p>