Video demo: https://www.youtube.com/watch?v=0z7QJxZWFQg
The first time I talked with AI santa and it responded with a joke I was HOOKED. The fun/nonsense doesn't click until you try it yourself. What's even more exciting is you can build it yourself:
libpeer: https://github.com/sepfy/libpeer
pion: https://github.com/pion/webrtc
Then go do all your fun logic in your Pion server. Connect to any Voice AI provider, or roll your own via Open Source. Anything is possible.
If you have questions or hit any roadblocks I would love to help you. I have lots of hardware snippets on my GitHub: https://github.com/sean-der.
IIRC, the 900 “area code” is still reserved for that kind of calling in the North American Numbering Plan, but all of the US carriers have withdrawn from doing pass-on billing for 900 calls (in part, IIRC, because the government prohibited them from disconnecting service for nonpayment of those charges), so I don’t think they’ve been a significant business for a while, and most of that kind of business has moved to various online platforms.