TW My sysadmin toolbox
I maintain a Web server using Apache 2, PHP, Perl, MySQL, and OpenSSL; an IMAP server running the up-and-coming RoundCube Webmail client; and a server for streaming MP3s. GNU Emacs, OpenSSH, TightVNC, and netstat are just a few of the tools I use to maintain my servers.
GNU Emacs is my editor of choice. Yes, I know a lot of people swear by Vim, which is more universally available, but Vim's shortcuts are just too unnatural to use with the Dvorak keyboard layout, which I prefer.
Being able to jump through a text file by character, word, sentence, paragraph, and page with just a few keystrokes saves a lot of time when editing long configuration files. I use Vim when I have no choice, but I feel much more at home in Emacs.
I also use the OpenSSH suite extensively, almost always used in conjunction with GNU Screen. With OpenSSH I can do almost everything remotely that I could do at the physical terminal itself. I make sure I never send passwords over the Internet unencrypted, so I sleep better at night knowing SSH is keeping my data secure.