I've been using Emacs recently, and it took me a while to figure out how to make option-3 produce a hash symbol like other Cocoa applications.
This assumes you're using mac-key-mode like this:
(add-to-list 'load-path "~/.emacs.d/mac-key-mode/")
(setq mac-option-modifier 'control)
To rebind the hash key, just drop the following in your .emacs:
(global-unset-key (kbd "C-3"))
(global-set-key (kbd "C-3") '(lambda() (interactive) (insert-string "#")))
Date: 26th November 2008.
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