AT&T offers several free services for people with hearing related disabilities, details are available at http://relayservices.att.com/, this service is funded by the FCC.
IM Relay is a solution for individuals who are Deaf, hard-of-hearing, or have speech loss. Request a phone number to be dialed and a AT&T Relay operator calls the phone number and translates the text to voice to the other party. There is no charge to use this service, but all users must register first.
Aside from using IM relay on PC or MACs, IM relay is accessible wherever there is AIM. Today, many mobile devices support AOL Instant Messenger applications. Just send the phone number you want to dial to the screen name "ATTRelay" and you can make calls on the go. Remember, there is no charge to use IM relay, but if you use a mobile device to access IM relay please check with your service provider to see if there may be any applicable data fees.Real world example