Alexander Moseson wrote:

A scientist is resurrecting 4500 year old technology from the pyramids to create a sustainable, environmentally friendly concrete. It produces 90% less CO2 than the standard Portland Cement, which is the second largest producer of CO2 behind fossil fuels. This could have huge applications in modern society, but even better, they hope to use it to provide cheap or free housing to developing communities all over the world.

(Alex is a graduate student working on the project.) Thanks for sharing Alex!