Black hole wheel.
Hubless design carbon wheel made in mid 90s, one piece wheel with a threaded 1inch steerer. The bearings go around the whole wheel, and this wheel was for indoor track use only. Manufactured in amount of 100pcs in total in mid 90s, was banned by UCI due to an unfair advantage it offered (literally almost ZERO drag), hence discontinued.
Not sure but I think they were made in 650 and 700c sizes, obviously tubular only.
I would do a lot to get my hands on something like this…