Another thing you can do in your Emacs is to send SMS messages using the Voovox service.
Emacs module provided by courtesy of Yoni Rabkin email@example.com
It's developed and supported by Yoni Rabkin and distributed under the terms of the GNU General Public License.
The latest version of the code will always be available at: http://yrk.nfshost.com/repos/diamondsms/diamondsms.el
It is also accessible via the Darcs revision control system:
darcs get http://yrk.nfshost.com/repos/diamondsms/
The code is in preliminary status right now, but I intend to develop it more as time goes on (I'm already expecting patches from two other developers who like the idea of sending SMS' via GNU/Emacs).