While at Singularity University attending the 2010 Graduate Studies Program, I learned about 3D printing and its applications in rapid-prototyping, manufacturing and design innovation.  Additionally, Astronaut Dan Barry discussed the potential to use 3D printers to drop launch costs to less than $1,000/kg compared to Space Shuttle launch costs of approximately $50,000/kg (other launch vehicles can deliver payloads to geostationary orbit for ~$10,000/kg).  For example, installing 3D printers in the International Space Station would allow ‘3D printing’ of replacement parts as needed.  This would minimize the cost resulting from having to launch spare parts into space.  3D printers with more complex printing substrates other than ABS polymers are being developed.