Image: Charcoal Briquette Maker

Give someone a bag of briquettes and they can grill for a week or two, but if you teach them how to make briquettes … well, then they need to acquire biomass, a 55-gallon drum, and some metal parts, but once they have those ….

All kidding aside, this is *wayyy* cool. [The MIT D-Lab site also has instructions on how to build and use your own corn sheller][mit]. By the way, MIT people, not everyone has access to welding equipment, but the design could easily be modified so that the tamper and the ejector are bolted together.