I work with GNU/Emacs since I switched to GNU/Linux and UNICES world (2001).
I really appreciated Emacs as a style of life with computers. There are some my papers in Russian are available on my web site: http://kulchitsky.org/rus/linux
There is ‘C-c’ keybinding prefix was left for users. However, I found there are many external modes use that so not so many free keys are available for user actually. Instead of ‘C-c’ I use ‘MM-’ key prefix for my own commands. I mean something like ‘ESC ESC’ prefix or ‘ESC M-’ prefix. It is really easy to “doubleclick” on ESC by left hand and then type a key by right one. Just try and probably you will like this too.
There are some keybinding I use.
(global-set-key (kbd "\e\el") 'goto-line) ; (global-set-key (kbd "\e\eu") 'user-cvs-update) ;PCL-CVS update start (global-set-key (kbd "\e\ec") 'calendar) ;calendar
and really many others. Sure, keybinding can depend on mode-hooks. My .emacs is available at http://kulchitsky.org/rus/linux/.emacs.