DuckDuckSheep.com allows you to send free anonymous text messages to your friends or contacts.
After you register and verify your account you can enter a contact's phone number and send an anonymous text message to their cell phone. The recipient of the anonymous text message will get a text message (SMS) to their phone telling them that they have a new anonymous message on DuckDuckSheep. The recipient can then reply to your message on DuckDuckSheep and you will get a notification that they have replied.
For more information visit http://DuckDuckSheep.com