Run 'say' command on Emacs

gistfile1.el

;;; Convert text to audible speech by /usr/bin/say (Emacs + OSX) 
(defun MyTeX-speech ()
  "Convert text to audible speech by /usr/bin/say of OSX."
  (interactive)
  (let (b e s
	  (block-sep-str "^\*\\|^\\ *%\\|^\\ *\n\\|\\\\item\\|\\\\begin\\|\\\\end"))
    (if (eq (process-status "speech") 'run)
	(delete-process "speech")
      (progn
	(if mark-active
	    (setq b (mark) e (point))
	  (setq b (save-excursion
		    (progn
		      (re-search-backward block-sep-str (point-min) 1)
		      (point)))
		e (save-excursion
		    (progn
		      (re-search-forward block-sep-str (point-max) 1)
		      (point)))))
	(setq s (buffer-substring-no-properties b e)
	      s (replace-regexp-in-string "\\\\%" "percent" s)
	      s (replace-regexp-in-string "\\\\item" " " s)
	      s (replace-regexp-in-string "\\\\begin" " " s)
	      s (replace-regexp-in-string "\\\\end" " " s)
	      s (replace-regexp-in-string "%[^\n]*" "" s)
	      s (replace-regexp-in-string 
		 "\\\\[a-zA-Z]+{\\|[$\\\\_^~(){}`*\n]" " " s)
	      s (replace-regexp-in-string "\\ +" " " s))
	(message s)
	(process-kill-without-query
	 (start-process-shell-command "speech" nil
				      "/usr/bin/say" (concat "\"" s "\"" )))))))

(define-key global-map [?\s-r] 'MyTeX-speech)

This function converts text in a marked region or a block sectioned by %s at the beginning of a line to audible speech. It works on Mac OS X (/usr/bin/say is required.)