Is there any cheap or free PHP interface for sending text messages?

Sending text messages costs money. Unless you send Fetion, it has nothing to do with language. The text messaging interface is just an address. You need to log in to get the sessionid, and then use it as a credential to send data to another address. That is Send text messages. So, as long as it can communicate remotely, it's fine. I've done one before, but it's not as fun as I thought. You pay for the interface