Appropriate technology, a social movement from the 30 years ago, is more often called "technology for sustainability" these days. It endures within wide ranging research and development efforts aimed at providing effective, low cost solutions to some important problems. A good example came to my attention recently from The Philippines.
According to its web page, "Isang Litrong Liwanag (A Liter of Light), is a sustainable lighting project which aims to bring the eco-friendly Solar Bottle Bulb to disprivileged communities nationwide" The idea originally came from a group of MIT students. In this simple design, used soda bottles are filled with water and caulked firmly into holes cut in roofs of small shacks and houses. Since water refracts light 360 degrees, the each bottle can produce the equivalent of a 55 watt bulb during daylight hours.
Further details and an interesting video can be found on the group's web site. Are similar concepts are under consideration for buildings of the developed countries? I don't know. Maybe I'll start drilling holes in my upstate New York house.