FrontlineSMS
From MobileHacking.org
FrontlineSMS is free (as in free beer) software - and open-sourced by the end of November 2008 - that turns a laptop and a mobile phone into a central communications hub. Once installed, the program enables users to send and receive text messages with large groups of people through mobile phones. What you communicate is up to you, making FrontlineSMS useful in many different ways.
Where to get this
Currently you can get a copy of the application by going Frontline's website and requesting one. It will be sent to your email address.
http://www.frontlinesms.com/download/
