Series of Tubes

Maybe I could have come up with a better title, but this one won't leave me alone, and I smile every time I think of it.

Anyway, here we see a vast network of tubes. We're actually seeing the inside surfaces of the tubes rather than the outsides. Half the tubes are large, and no large tube intersects any other large tube. The other half of the tubes are small, and they serve as connectors between the large tubes. Silver ellipsoids journey along inside the large tubes for some reason. What it all means is left entirely to the imagination of the viewer.

See also, in 3D:
Red/Cyan version
Green/Magenta version