They don't know it by name, but if you tell them that with IPv6 they could ditch their mobile phone service (their home router can run a SIP trunk just fine, so

They don't know it by name, but if you tell them that with IPv6 they could ditch their mobile phone service (their home router can run a SIP trunk just fine, so all they need is a non-NATed connection), or that you could create a FON-style mesh network where you could make money by becoming a hotspot provider, they would be more interested.