Sonobus is a software project that tries to accomplish live, audio-only multi-player jamming over the public network.

It's still limited to whatever latency the network has, but it can be useful for some things. If that means it's mostly useful for loops, then that's up to the musicians. :)

(I myself have used it for remote livestream participants, but only for voice. I was able to get distinct inputs into my console just like folks in the studio had, and I gave them a mix-minus bus that included everyone's voice but their own, for their headphones.

It worked slick. Interaction was quick and quality was excellent. And unlike what popularly passes for teleconferencing these days: It all flowed smoothly and sounded like they were in the room with us, even though they were a thousand miles away.)