The world's smallest guitar is 10 micrometers long -- about the size of a single cell -- with six strings each about 50 nanometers, or 100 atoms, wide. Made by Cornell University researchers from crystalline silicon, it demonstrates a new technology for a new generation of electromechanical devices.
The guitar has six strings, each string about 50 nanometers wide, the width of about 100 atoms. If plucked -- by an atomic force microscope, for example -- the strings would resonate, but at inaudible frequencies.
The entire structure is about 10 micrometers long, about the size of a single human blood cell.
A nanometer is one-billionth of a meter. For comparison, the diameter of a human hair is about 200 micrometers, or 200,000 nanometers.
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this one is a bit more practical ... just
http://www.youtube.com/watch?v=jU85K3B6Brs
