This might stretch Wayne´s original idea somewhat, but right after WWII German cycle manufacturer Rixe made cycle repairstands, those real heavyweight ones two mechanics can work on opposite each other. The top
tubes of the bikes would be held by clamps and a heavygauge tube was going down into the tip of a concrete shaped steel shell, about a foot
or more in diameter and about two feet high which looked suspiciously like the upwards pointing sawed-off nose half of a high explosives aerial bomb, which it actually was.
Regards, Toni Theilmeier, Belm, Germany.
P.S.: This is not an urban myth; these stands surface from time to time
and I saw one myself only some months ago. I guess I´ll not make the
joke about bikes having been repaired on them going like...