Yup. I don't use tramp that much (well, in the last 4 months I used it daily, but...), but having it is great. Every time I have to edit more than 4 lines in a server I resort to it (if it's less I use nano or vim, because it usually means I'm in a ssh session editing some config file)
TRAMP mode: http://www.emacswiki.org/emacs/TrampMode
I do plenty of work over ssh, and this saves me the headache of dealing with screens and multiple terminals.