Thanks for the comments, Kiramishead, Altantis, Shasvre and Mr Space Jockey.
I guess we'll have to see where that idea goes next. I often keep imagining them marching through a high tunnel as a hologram carrying that thing.
I also keep thinking about how Giger has with his Space Jockey type biomechanoids had the pipe extending from the bottom of the chin as if it were a beard, as with his picture Atom Kinder, so I included a pipe beard on the tall figure on the right and had it ending in a snake head.
