In the parts of the world that are relevant to me, anyway, which is GNU/Linux and BSDs.
On Windows you can use it with putty and Xming, on Mac there's also an Xserver which you can definitely use for this... Though I don't know whether these would also work for a server, but who wants non-*NIX on a server anyway.
SSH by itself allows you to run commands on another machine. Together with Vim (or a good console text editor) and Tmux (for window management), you can just connect to your development machine, code and test. This allows to continue where you left off and instantly work.
SSH has the ability to create forwarded port mappings, SOCKS5-compatible proxies and perform file transfers, without the need for additional tools or permissions.