That looks great, do you have a list of parts used for the setup?
The bottom rectangle is 12" x 24", and then the top/side pipes are 36" each.
It's a bunch of steel pipe from Home Depot, and sturdy enough you could do pullups on it. The pipe isn't super cheap, was around $200 total I think. I went with 1 inch diameter because it would hold the monitor arms better, but you could go thinner and cheaper with a different monitor mounting solution.
Somehow a search this morning sent me to Pinterest with a lot of photos of decorative knots. That might be a way to do some joins between crossbars, as well. (I hear macrame is coming back!)