While:

…nanostructures are building blocks for many important technological advances, including high-performance solar cells and batteries, new methods of diagnosing and treating disease, next-generation computer processors and memory, and lightweight composite materials… [from Nanobama.com ]

you can also use them to create nifty structures like the Nanobama above, just for fun. Note that each of the Obama faces shown is made up of about 150 million nanotubes – about one for each person who voted in this election. And for scale: each face is only about 0.5mm wide (about 10 hair-widths). Created by a team at the University of Michigan.

See also: Mechanosynthesis.