Soda bottles filled with water and placed in holes in the corrugated roof acting as light pipes. Neat idea.
However — each will come to leak, the plastic doesn’t last forever, and the roof will come to leak around them. They only work in sunlight, and would freeze in places where freezing temperatures occur.
Net out? Stick with skylights.
Definitely a 3rd world solution.
But as mentioned, a potential winner in the upcoming Baraqqi Depression.