Put this in your .emacs file
(setq mac-option-modifier 'super )
(setq mac-command-modifier 'meta )
I also use the System preferences to map the Caps-Lock key to Ctrl - A lot easier especially since a lot of keyboards tend to move the CTRL key aroundWhen I really need to get writing at home, I plug in a MS N4K and go at it.
I'd thought for a long time that Fn was a hardware/OS-only key based on the lack of apps that use it, but it seems Emacs has found a way.
So, I use option for 'alt', but here's the great thing. You can use the command key for other stuff! I've got keybindings for my most common actions.
command-j -> ido-find-file
command-d -> anything
etc
(global-set-key "\C-x\C-m" 'execute-extended-command)
(global-set-key "\C-c\C-m" 'execute-extended-command)Sure, this is an invasive change, but it saved me from RSI.
It's been pretty difficult as I am a dyed in the wool VIM user. Someone on HN recommended the Evil plugin (http://gitorious.org/evil/pages/Home) for an approximation of VIM movement and other bindings. It surprisingly works pretty well. It's letting me remain productive while I slowly adapt to the emacs key-bindings over time.
I am using emacs-prelude as well (https://github.com/bbatsov/emacs-prelude) which is a startup scripts kit.
I'm still not sold on emacs yet, but I am giving it time.