These are hard to explain. Basically, the mind-blowing thing about them is that the upper and lower structures are completely unconnected — except by dental floss under tension. It seems to defy logic and physics, since it never collapses-in on itself under tension or the force of gravity.
Weirdly, you could flip it upside-down or lay it on its side and it would still hold together without collapsing.
You can learn more about tensegrity structures here or here.
This would look more impressive with black thread, but I used white dental floss so you could see the strings.