I just asked about that. Now I look stupid. Answer first, then question.
C3 is free but it does require you to register. It really hasn’t caught on outside of the gaming community. It allows you to create a chat room and it assigns it a phone number that people can call it to so you can have people on their computers and folks on their phones in the same session together.
You dont look stupid, no worries. It’s easy to miss things when people start commenting.
"...if stupid cost money we'd all be broke"