I've developed a daemon in PHP that is effectively an SMS-to-email (and vice versa) gateway, using VoIPo's web-based SMS interface as a sort of API. If I send an email to 2125551234@sms.mydomain.com, it turns the first 160 characters of the message into a text to the number 2125551234. If I receive a text from 2125551234, I get an email from 2125551234@sms.mydomain.com

I've been using it for over a year, and it's just great. If anyone out there wants the script, just ask. You'd need some modest PHP skills to implement it and adjust it for your needs. Some understanding is also needed of how to set up PHP, and how to create a cPanel-Chron or Windows Scheduler job.