London design student Markus Kayser has taken playing with a magnifying glass to a whole new level with his solar-powered 3D sand-printer. The "Solar Sinter" uses photovoltaic cells to provide power for the electronics, and a giant lens focuses the sun's energy to a point so hot, it melts sand into glass. The machine prints 3D objects designed in a CAD system by moving a box of sand around under the focused light. Each layer of sand must be poured on and leveled by hand as the object is melted into existence from the bottom up — motors and sensors keep the lens and solar cells pointed directly at the sun during the lengthy process. This thing would never work in foggy England, so Kayser tested the apparatus in the Sahara for obvious reasons. Check out the video of this contraption in action below.