Switching flyspell dictionaries on the fly

Since I am using Emacs for most of my text processing, and it comes with the nice Flyspell mode, and I do write English and German the most, I found this nice snippet from the Emacs wiki:

(defun fd-switch-dictionary()
    (interactive)
    (let* ((dic ispell-current-dictionary)
    (change (if (string= dic "deutsch8") "english" "deutsch8")))
      (ispell-change-dictionary change)
      (message "Dictionary switched from %s to %s" dic change)
      ))

(global-set-key (kbd "<f8>")   'fd-switch-dictionary)

On OS X, I recommend to use emacs-app or emacs-app-devel from MacPorts. For flyspell to work correctly, also make sure to install aspell and e.g. aspell-dict-de. Otherwise the above function will complain, most probably.