There are other things with a similar concept. The core JS behind this is a couple hundred lines at the worst.
I really prefer p2p if available, and on my LAN it doesn't have to traverse NAT or anything.
Or just start poking through their code and WebRTC docs/libs to see what you can build yourself.
We do NAT traversal but also connect to local peers over multicast DNS. Command line client should have a local or offline option to restrict only to local peers soon.
=)