DesktopSMS is an application for Android who allows you sending text messages (SMS) from your computer through your Android phone. DesktopSMS is composed by two applications : a client on your computer and a server on your Android phone. These applications are written in JAVA.

You can access to your phone contacts, sent SMS and received SMS, all of this on your computer. Thus, with this application, you can send an SMS easily and quickly, because you use the keyboard of your computer.

http://code.google.com/p/desktopsms/