Like how SSH agent forwarding can allow you to hop from box to box with the SSH keys loaded onto your local machine's SSH agent? Found that one a few months ago, made me reflect on what I've been doing in life the past 10 years not thoroughly reading UNIX man pages.

Thanks for this one. You just added a few days to my life and helped push out the onset of carpal tunnel/arthritis. ~ http://www.unixwiz.net/techtips/ssh-agent-forwarding.html

ssh is magic. checkout -X for X11 forwarding to run remote GUI apps, and -R which lets you set up a reverse SSH tunnel when you need to connect to a machine behind a firewall.

such a polite version of RTFM, i love you