I'm over at Code for America ( http://codeforamerica.org ) and we've got an app ( https://github.com/codeforamerica/balance/ ) built on Twilio that lets people on food stamps check their EBT card balance via text message.
In ~3 weeks we've got almost 300 successful balance checks so far!
We're trying to expand to states outside California, and I'm bumping up against a tricky issue with some states:
Right now, we're triggering an outbound phone call with sendDigits
to navigate the phone tree.
(For example, wait 2 seconds, press 1 to select English, wait 2 seconds, enter the client's EBT card number)