gistfile1.el

(defvar *twitter-auth* "user:pass")
(defun twitter-update-with-curl (stat) (interactive "sTwitter: ")
  (let ((twit "-d source=curl http://twitter.com/statuses/update.json")
        (stat (si::www-url-encode (map-internal-to-utf-8 stat)
                                  nil "-0-9A-Za-z._~")))
    (message "~D" (execute-shell-command
                   (format nil "curl -s -u ~A -d status=~A ~A"
                           *twitter-auth* stat twit)))))
(global-set-key #\C-\\ 'twitter-update-with-curl)