The IETF has done this before. ST-II, documented in RFC1190. Technically it is IPv5. I documented an even better protocol, at the link layer, in RFC2549.

As a followon to my rfc1149 and rfc2549, I considered doing IP over black holes: if you carefully control matter being dropped into a black hole, you can modulate the huge X-ray emissions as the matter is ripped apart. This would be detectable over huge distances.