Isn't this basically the payment protocol? And this is only tangentially related but I feel it would have been good to pursue a pronounceable, Urbit-like alphanumeric encoding of addresses such as "machec-binnev-dordeb-sogduc--dosmul-sarrum-faplec-nidted" (which represents 128 bits in Urbit) in the first place but I guess it's too late now.