SMS Send & Receive lets you send and receive SMS messages using a simple REST-like web API. With your personal API key you get 1000 free SMS messages that you can send using the API, as well as a keyword for receiving SMS messages sent to your service.
Update 8/29/11: Unfortunately the SMS Send & Receive API is still down. Due to problems in one of the modules we have been forced to bring the service down for an extended service break.
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