One of the most exciting use cases for Synthetic Biology is in space and on other planets.
Check this cool article about developing bacetria and other life forms to teraform mars: http://www.newscientist.com/article/mg21628855.100-build-a-mars-base-with-a-bug-box.html
From the article:
THE next time humans set foot on an alien world, they may not travel alone. Small, lightweight "bug boxes" packed full of engineered microbes could make life on hostile planets a lot more liveable.
Pioneering settlers on a distant world will require food, fuel and shelter if they are to survive, but bringing bulky supplies from Earth is far too costly. Synthetic biology offers another option. Microbes weigh precious little, and would take up next to no space on a spacecraft, but once the mission lands - on Mars, say - they could multiply by feeding on the materials available there. The products of their labour could provide the building blocks essential for a human settlement.
NASA has already begun research to realise this dream, says Lynn Rothschild at the Ames Research Center in Moffett Field, California. Rothschild is leader of NASA's new Synthetic Biology Initiative, which aims to build designer microbes for future crewed space missions. She shared her vision at last week's BioDesign Forum in Cambridge, UK.