This is exactly what it sounds like. I wanted to experiment with the Twilio API, and this seemed like a quick and easy application to make.
Call (480) 878-7813 and you'll randomly be connected with anyone else who is currently calling the same number.
If you're interested in a more detailed write-up, click here.
$> shotgun config.ru
TWILIO_PHONE_NUMBER= "(xxx) yyy-zzzz"