Low-cost metal 3D printing?

I have been wondering about all of the possibilities of 3D printing with metal. I spent some time as a child alone, homeless, and collecting aluminum cans, so recycling comes to mind. I have developed a passion for sustainability and technology as well as lowering the barriers to entry for people wanting to start their own businesses. I also saw this video on using fresnel lenses and melting metal. https://www.youtube.com/watch?v=drE54ctrHBY I have a background in metal casting and I wondered what could be accomplished with open-face molds.

I have a number of things I have considered, but none of them involved vibration like the way these folks are doing things. They are 3D printing metal without using very expensive equipment such as lasers or special powdered metal to achieve some impressive initial results. They are saying they just need to swap out the print head to get the results which sounds like there are a lot of home-use printers that could be a potential market as well as commercial applications. What intrigues me is the potential for this application in developing nations, war zones, and disaster recovery. I have no idea what it is going to cost, but I am a manufacturing engineer, and my first glimpse and rudimentary understanding of how it works leads me to hope that this will be a low-cost option for 3D metal printing.