[JRios1968]

Andrew Young, though, says Stonehenge's slabs, may have been rolled over a series of balls lined up in grooved rails, according to a November 30 statement from Exeter University in the U.K., where Young is a doctoral student in biosciences.

I bet he's related to Angus Young of AC/DC...

[SunkenCiv]

Probably the prehistoric inventor of this system had a last name of Hall, hence, Hall’s Balls.