For 3-D food printers, chocolate is a good material to start with, because it's fairly simple to make it liquid inside the printer cartridge and solid once it drops out. Courtesy of Smart Gastronomy Lab, University of Liège hide caption

itoggle caption Courtesy of Smart Gastronomy Lab, University of Liège

Jake and Natalie Peterson and their son Garrett in October 2014. Courtesy of Brittany Jacox hide caption

itoggle caption Courtesy of Brittany Jacox

Andy Leer of maker space chain TechShop calibrates a 3-D printer at a GE-sponsored pop-up workshop in Washington, D.C. Maker spaces, which offer access to industrial-grade tools, are attracting support from governments and big companies like Ford and Lowe's. Gary Cameron/Reuters/Landov hide caption

itoggle caption Gary Cameron/Reuters/Landov

A mathematician's sweet dream: For about $10,000, you can print out rainbow sugar dodecahedrons and interlocking cubes. 3D Systems hide caption

itoggle caption 3D Systems

A simulated patient at the University of Malaya makes use of different materials to mimic the look and feel of human tissue. /Courtesy of Vicknes Waran hide caption

itoggle caption /Courtesy of Vicknes Waran

Cosmo Wenman generated this 3-D model of the Ares Borghese, based on hundreds of photos, from the Basel Sculpture Hall. Wenman publishes the scans online, so that anyone can use them to 3-D print a replica of the masterpiece. Courtesy of Cosmo Wenman hide caption

itoggle caption Courtesy of Cosmo Wenman

Toronto-based 3-D jewelry company Hot Pop Factory created personalized Pez dispenser heads for the employees of an architecture firm. Hot Pop Factory hide caption

itoggle caption Hot Pop Factory