I’m on a long haul flight right now from ORD to PVG, and was excited for some no-distraction time to get some work done. (The $16 wifi on United, although slow and its coverage spotty, is worth every penny.)

$ git fetch
ssh: connect to host github.com port 22: Operation timed out
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

Grr. Port 22 is blocked. Fortunately, you can access Github over port 443 easily:

In ~/.ssh/config, simply add:

Host github.com
  Hostname ssh.github.com
  Port 443

and voila!