Sometimes when You are developing locally You might want to connect to a remote server without opening up a lot of ports on the server.
This is a simple trick to easily access services on a remote server without exposing the actual ports on the server.
$ ssh -N -L 1234:localhost:1234 email@example.com
The above means map port
1234 on localhost to port
1234 on server
NOTE: The above will only work if You have proper credentials and SSH access to the server.