SSH flags I don't use for tunnelling

Short one today. When tunelling into a remote server using SSH, I used to use -NfL. -N doesn't run a shell, -f goes into the background, and -L is used to forward a local port to a remote one. But nowadays I just use -L. That way, to check if the connection is still up, I can just press Enter on the shell prompt and get a quick sense of the latency to boot. And of course you can't do that if the connection is in the background.

-D is useful too. It opens a SOCKS proxy on your local machine, which in turn lets you point your browser's proxy settings at your local machine to use for censorship circumvention or as a VPN to access your remote's local network or whatever.