A team at MIT has been able to use a genetically engineered virus to help build carbon nanotubes, microscopic cylinders that are integral in constructing high-efficiency solar cells. These nanotubes had proven difficult to construct due to their small size, and traditional techniques were doing a poor job. However, a virus that was custom made for the job was able to build the nanotubes relatively easy and with a significantly higher level of efficiency and is a promising new technology for the environmental industry.