An app which allows you to send SMS messages via an HTTP request. Connect the phone to WIFI to get an IP address, open the app and find out the address of the new SMS server. Browse to the address for more instructions, or simply make a request to http://address/?number=1234&message=my%20new%20message to send an SMS via the phone.
The app also stores a log of sent SMS messages, and listens to WIFI changes to automatically reconnect in case of a change.
Longer SMS messages are automatically split to the allowed length.