title: Limitations on SMS messages sent using free email->SMS gateways
body: <p>Many cell (mobile) phone providers in the USA have an email gateway for SMS that allows anyone to send an email that will in turn send a text message. For example, to send a text-message to a user who has a Verizon phone you can send an email to user_phone_number@vtext.com.</p>
  
  <p>But... how reliable are these gateways, and what limitations are there on the rate of messages that can be sent? At some point do the providers block or throttle service? </p>
  
  <p>Is there anyone out there who is using this type of email/SMS gateway for either a high volume or high reliability application?</p>