One of the most asked stuff I get is how to access to the office computer from the outside world when there’s just one point of access. This involves ssh-ing one machine (main server of the university/institute) and then ssh-ing your machine (behind the wall).
Tunnelling is very useful for have quick access to it, but most of all when you need to transfer files from one to other, check your mail with your mail program, or even use github* (in that case is normally in the opposite direction, from my work machine to a external repository).
Also, using ssh-keygen to generate the public key is very helpful if you don’t want to type the password each time.
Would this be a good 3-minute screencast?
- of course, github allows you to access to it through https too.