In the opposing vein, as an Emacs user the best configuration I ever made was to rebind C-x C-c to execute-extended-command instead of kill-emacs. It was way too easy to (even accidentally!) kill emacs with a sweep of a finger. And I probably use a few hundred execute-extended-command calls for each kill-emacs (which I now have to type manually as 'C-x C-c kill-emacs' - no problemo). A similar optimisation was with t…
> A similar optimisation was with tmux to bind the prefix to C-z. It's in a handy location next to ctrl and I very rarely use suspend anyway. I think gnu screen has the right idea here: ctrl-a. And you say z is close to control - does that mean you use emacs without shift lock as control?! (I mean sure, still closer than b...).
C-a (like in screen) would be even better but as others have pointed out it masks going to the beginning of line which is very common.
C-z is very rarely needed. C-q/C-s would be good candidates also as I don't think I've ever needed flow control in this century nor the last one, for that matter.