"Proctologically Violated©®"
wrote:

Cheapness is in the eye of the beholder.

Agree

What I'm looking for is kind of a poor mans adult
"erector set"

Someone else suggested using Unit strut....and there
products would work just fine

But I'm trying to think out of box here and use
something modular, cheap, and scalable,

Again.... goal is to create all sizes and shapes of
internal structures in a room. Structures capable of
supporting some weight and used to hang a variety of
things from.